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Messages - jrista

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1471
EOS Bodies / Re: EOS 7D Mark II Announcement in Q2 of 2014 [CR1]
« on: February 28, 2014, 03:33:34 PM »
People seem to be suggesting (not just on this forum) that Canon are scratching their heads over the potential specifications of a 7D Mk II. I'd have thought that it was pretty obvious -an APS-C sensor version of the 5D Mk III with a higher frame rate (i.e. 8-12fps).

The elephant in the room is whether the 20MP sensor from the 70D is good enough for their "flagship APS-C camera" or whether Canon are waiting to launch a new generation of sensors in the 7D Mk II. The more time passes from the 70D's introduction, the more likely I think the 7D Mk II will be the launch vehicle for the new generation of sensor; I would therefore expect any announcement to be just prior to Photokina. [Sod's law they will announce it next month and make this prediction wrong!  ::)]

Purely speculation but I would imagine one of Canon's biggest concerns is a new 7D Mark II potentially eating into 1D X and the big white market. They need to make it attractive enough, but not so attractive to take away any of the market from their flagship body and lenses.

This is such an old and tired argument. Canon has nothing to fear from the 7D II stealing from the 1D X. The 1D X is going to be a superior camera in every respect. If someone can afford it and wants the best quality they can get, they are going to get the 1D X. In my previous comment, I explain why. Ultimately, noise is more about sensor area than pixel size. When it comes to pixel peeping, pixel size matters, but pixel peeping isn't photography...it's just a waste of time. FF sensors have more total area than APS-C sensors. For identically framed subjects, that means FF always has the potential to gather more light. More light, less noise. If you choose to stop down, then that is an artistic or technical choice, not a limitation of the technology.

In no way, regardless of what features Canon puts into the 7D II or how good they are, will it ever really steal sales away from the 1D X. On the contrary, by making the 7D II as good as they possibly can at the cheapest price point they can, it will GREATLY increase their sales. The simple fact of the matter is many, many people would probably LOVE to have a 1D X, they simply cannot afford it. The biggest thing stealing sales away from the 1D X is it's price. A feature-rich, highly capable "Mini 1D X" in the 7D II would give all those people a far more affordable option that is in reach...increasing total DSLR sales.

1472
EOS Bodies / Re: EOS 7D Mark II Announcement in Q2 of 2014 [CR1]
« on: February 28, 2014, 03:28:57 PM »
Seeing as the D4s is coming with a 'new' 16 mp sensor, I'm going to be brave and guess the 7DII will also be 16 mp, aps class leading low light performance, very fast and no pop up flash. See you in the second quarter.
Please God hear our prayers. Only 16 megapixel camera with ISO 3200 without noise bothering, costing less than $ 2000.

I'd rather have 24, 32 or even 72MP.  More resolution and less noise that way.

That's a misconception. If you account for noise as a factor of total sensor area, it doesn't really matter how large or small your pixel are. The expectation is that you are downsampling any and all of those sensors to some common output size...i.e. the same magnification.

Otherwise, smaller pixels are always going to have more noise at the pixel level. Any technology you might apply to smaller pixels is applicable to larger pixels. Any potential technological gains you might have that allow smaller pixels are only going to make bigger pixels better. In no way can smaller pixels be less noisy than larger pixels. They may resolve more detail, but assuming Q.E. remains roughly the same, that detail WILL be noisier.


All else being equal, if you have 6 micron pixels and 3 micron pixels, the 3 micron pixels are going to have 1/4 the FWC. A 6 micron pixel might have 60,000e- max charge at ISO 100, where as a 3 micron pixel is going to have 15,000e- max charge. Since noise is the square root of the signal, you have 244e- noise with 6 micron pixels, and 122e- noise with 3 micron pixels. In other words, you have a 244:1 SNR with 6 micron pixels, and a 122:1 SNR with 3 micron pixels.

The only way to make those smaller pixels equal to the larger pixels is to downsample by a factor of two.

What's the problem with having a high resolution sensor that allows detailed images at low ISO and then downsampling to reduce noise when you need to used higher ISOs?

I'm asking because you seem to know your stuff and I'd like to get this cleared up once and for all!

Oh, there is absolutely nothing wrong with it. It just won't give you LESS noise. Assuming we have two APS-C sensors, if we view them a 100%, the image taken with the sensor with smaller pixels will be noisier. If we sample them to the same size, noise will be equal. The sensor with smaller pixels will be crisper when scaled to the same size, but there won't be any real difference in noise.

Why? Because both sensors have the same total physical area. Assuming the same output magnification, the only thing that matters is sensor area, not pixel size.

This is a different argument than FF vs. APS-C. In the case of FF vs. APS-C, you can look at it a couple of ways. There is equivalence. You frame the same scene identically with both FF and APS-C (doesn't matter if you get closer with FF or use a longer lens). You need a narrower aperture with FF in order to achieve the same DOF as APS-C. You end up with the same amount of noise for the same output magnification. Again, total sensor area matters here, however you have normalized all factors, so noise relative to output magnification is going to be similar.

However, I don't think that is generally how photographers think. In my experience, photographers who want the same framing with FF as their APS-C counterparts ALSO want a thinner DOF and blurrier background. That is especially the case with those who do portraiture, weddings, studio work, etc. with shorter and medium focal lengths. In that case, FF is always going to be vastly superior to APS-C. Not only do you have greater total sensor area, but you have larger pixels AND a faster aperture. No contest. Smaller pixels on a smaller sensor cannot compete in any way, shape, or form.

In any case, in none of the above scenarios will smaller pixels give you BETTER noise characteristics. They may allow sharper images, but from a noise standpoint, you at best can get the same noise performance out of smaller pixels for the same sensor size. Smaller pixels on a smaller sensor, in common use cases they will never be as good as larger pixels on a larger sensor, and at best they will only be "as good".

1473
EOS Bodies / Re: Will the next xD cameras do 4k?
« on: February 28, 2014, 03:01:51 PM »
4K video is now featuring on SmartPhones:
- Sony Xperia Z2 brings 4K video to its flagship smartphone
http://connect.dpreview.com/post/4506883679/sony-xperia-z2-records-4k-video
- Samsung Galaxy S5 adds 16MP camera with 4K video
http://connect.dpreview.com/post/7372383200/samsung-galaxy-s5-features16mp-and-4k-video

Will the 7D Mark II be the first "normal" DSLR with 4k video??

I think Sony and Samsung have every reason to put 4K in their phones, given that they have 4K televisions to sell as well. Its an incentive, buy one and get the other one because its compatible with each other. I can see the advertisements now: Don't have enough 4K content yet? Thats fine, make your own 4K content with our phones. Then buy our TVs to view your 4K content.

In my opinion, get yourself a GoPro 3+ black edition... borrow one... buy one, use it for a week or 2 and return it.
Test it out... Record 4K and see what you can actually do with it. I know its not exactly 4K at the desired frame rates that you want... but you will see how limited you are with it.
Just do it... it will explain every thing I was saying up till now.

Well, I shoot video and I don't use a cell phone to do it. Trust me, 4K will be a big improvement over what we have now.

Remember, even if you are delivering in 2K, having your source footage in 4K is a significant advantage in many ways.

This is very true, for sure. However it also kind of assumes you know why it is an advantage, and that you have the post-processing software to take advantage of it. I still don't see this as a reason for Canon to put 4k in all of their DSLRs with upcoming releases. It might be grounds for them to release firmware updates for the 1D X and 5D III to support 24fps 4k, though.

1474
EOS Bodies / Re: Is Dual Pixel Tech Coming to the EOS 5D Mark III?
« on: February 28, 2014, 03:00:11 PM »
I thought Magic Lantern had already done this with the 5D3??

cayenne

Dual pixel tech is a hardware feature. It cannot be added with firmware. Canon would have to have actually manufactured the 5D III sensor with dual pixel technology at the time they released it in order to add the capability with a firmware update later on.

Given the work that ML has done, if that was the case, I would have expected them to have figured that out by now, what with all of the things they have been doing with the 5D III lately. Given that they have not, it seems unlikely that the 5D III sensor was actually manufactured with DPAF tech.

If Canon does offer an upgrade, it would be a "Send your camera in and we'll replace the main board with one that has a DPAF sensor". And, that would probably cost a pretty penny, too! They may release an interim update to the 5D III, like the 5D IIIdp, that includes just a new sensor and no other model changes. Canon has done small interim camera model updates in the past, like the 1D IIn.

1475
Landscape / Re: Deep Sky Astrophotography
« on: February 28, 2014, 01:25:27 PM »
Having not even read all of that yet, and doubt I will tonight...let me just say that, I think you knew I was being sarcastic, because that actually is really what I think of you.  And I know you think even worse of me, so I know you were also being sarcastic.  But it's kind of fun to not let our personal mutual disgust get in the way of other important things such as photography.

I also wanted to say that, having not thought much about what I asked above (apparently), I can answer my own question with a simple answer (as in, why not get a scope instead, etc.).

(Besides the fact that you are a birder)...It's because you want a wider field of view than most telescopes provide, correct?  I'm pretty sure most of the astro images I've seen, that needed a wider field of view, were not shot with telescopes, but rather SLR cameras and lenses.

There are some very good short focal length refractors out there specifically designed for wide field work. There is also the HyperStar option for Celestron SCT scopes, which focal reduces them to f/2 instruments. If you have a 2800mm f/10 11" EdgeHD, and convert it with Hyperstar, you now have a 560mm f/2 imager...that is an even wider field than I get with my 600mm. Some refractors are as short as 400mm.

I think a lot of people DO use their camera lenses for very wide field work, for sure....although I think that is more a matter of convenience than anything. A good apochromatic 80mm f/4 scope (320mm focal length) can cost a pretty penny (several thousand), where as a 300mm f/4 camera lens might cost $1000 cheaper (although can still cost a thousand or two itself.) The actual apo 80mm f/4 refractor will be a much better device for imaging, and if y our serious about your astrophotography, it's the better route to go for wide field work (unless your talking Canon Great White telephotos, in which case until you get to the real high end range of apo scopes, the Canon lenses will be better.)

There are actually some professional scientific groups that use arrays of Canon lenses to do deep sky imaging. I know that EF 200mm f/1.8 L and f/2 L, EF 300mm f/2.8 L, EF 400mm f/2.8 L lenses have all been used in ultra fast (i.e. f/1!) telescopic arrays. Some have been used to find ultra dim deep field objects (super distant, dim galaxies), others have been used to find the dimmest nebula and galactic disc detail ever (the size of the average galaxy, according to some papers about an array that uses 12 EF 400mm f/2.8 L lenses in an f/1 setup, is significantly larger than is normally seen in your average visible light imaging...at f/1, you can gather so much light that you can see the dimmest structures in the universe with the exception of what Hubble itself sees.)

Ok, I read some of the end of one of your posts.  9 micro meters for a pixel on a medium format imager...impressive.  Would you happen to know what sort of imagers some of the well known observatories use?  I'm sure it's probably customized, or "bespoke" componentry, but was just curious.  I imagine the sensor is even larger than medium format.  The one in the Hubble Space Telescope I assume, is quite large, but probably not the largest.  Perhaps the "wide field" space scope uses an even larger imager (the one that hunts extra-solar planets, detects phase shifts from stars)...I think this is not even really called an imager, is it?

Hubble has some large imagers, but its newer and more advanced ones are not all that large. Certainly not the largest.

A lot of professional observatories use PlaneWave scopes on Paramount ME II mounts with FLI imagers as the lowest end imagers they might use. There are some much larger imagers out there. Some have diagonals as large as 90mm, which is utterly massive, that's a 64mmx64mm sensor. These sensors also tend to have around 70dB of dynamic range. When you factor in a multi-stage watercooled TEC with a 70°C to 80°C Delta-T and read noise levels in the 0.001e- range, and they utterly blow the crap out of your average DSLR sensor or even a cooled $10,000 astro CCD imager. Imagers like that tend to cost a hundred grand a piece.

The larger PlaneWave scopes, including the $200,000 28", have become pretty standard these days for professional installations. They are usually set up as arrays and calibrated to point at the same locations in the sky synchronously. So, you might have an array of five PlaneWave 28" CDKs all with the high end 65mm or 90mm (diagonal) sensors. Your average multi-scope array setup for a university probably costs a couple million bucks, but in terms of combined relative aperture and sensitivity, such a setup can rival a mountain top observatory for total light gathering capacity, at a tenth the cost or less.

The largest telescopes on earth, like the Keck 10 meter, is an f/1.74 monstrosity. The Keck observatory houses multiple scopes, uses active optics, and dozens of imaging devices. I doubt any branded cameras were used...they probably use sensors from Teledyne, E2V, etc. and built them directly into the system.

1476
Landscape / Re: Deep Sky Astrophotography
« on: February 28, 2014, 01:09:36 PM »
The Pleiades. The first few frames I managed to get on the first night I set up my telescope setup:



This was stacked from only a few frames, maybe 28. I had originally intended to take about 100 frames or so, but cloud cover and an accidental unplugging of my power cable ended up ending the night before it really got started.

1477
EOS Bodies / Re: Will the next xD cameras do 4k?
« on: February 28, 2014, 12:55:52 PM »
There is no way the 5D III is being replaced this year. Not a chance. It's a SUPERB camera, and the 5D II lasted closer to four years than three. I don't expect to even see CR2 rumors for the 5D IV until next year, and I don't expect it to hit the streets until the end of 2015/early 2016. The 1D X won't be replaced any time soon, either...it's just too good a camera. It would be unwise for Canon to release new models for at least another year and a half (especially considering the 1D X didn't actually hit the streets until the better part of a year after it had been announced.)

The 5DIII development cycle was interrupted by environmental factors: the tsunami at Fukushima delayed quite a few products meaning that the 5DIII would have arrived sooner than it did if everything had of gone to plan. 4 year gap was likely not intentional.

That still does not change the fact that the 5D III is still an exceptional camera by current standards. It will continue to be an exceptional camera for many more years.

1478
EOS Bodies / Re: EOS 7D Mark II Announcement in Q2 of 2014 [CR1]
« on: February 28, 2014, 04:39:49 AM »
Seeing as the D4s is coming with a 'new' 16 mp sensor, I'm going to be brave and guess the 7DII will also be 16 mp, aps class leading low light performance, very fast and no pop up flash. See you in the second quarter.
Please God hear our prayers. Only 16 megapixel camera with ISO 3200 without noise bothering, costing less than $ 2000.

I'd rather have 24, 32 or even 72MP.  More resolution and less noise that way.

That's a misconception. If you account for noise as a factor of total sensor area, it doesn't really matter how large or small your pixel are. The expectation is that you are downsampling any and all of those sensors to some common output size...i.e. the same magnification.

Otherwise, smaller pixels are always going to have more noise at the pixel level. Any technology you might apply to smaller pixels is applicable to larger pixels. Any potential technological gains you might have that allow smaller pixels are only going to make bigger pixels better. In no way can smaller pixels be less noisy than larger pixels. They may resolve more detail, but assuming Q.E. remains roughly the same, that detail WILL be noisier.


All else being equal, if you have 6 micron pixels and 3 micron pixels, the 3 micron pixels are going to have 1/4 the FWC. A 6 micron pixel might have 60,000e- max charge at ISO 100, where as a 3 micron pixel is going to have 15,000e- max charge. Since noise is the square root of the signal, you have 244e- noise with 6 micron pixels, and 122e- noise with 3 micron pixels. In other words, you have a 244:1 SNR with 6 micron pixels, and a 122:1 SNR with 3 micron pixels.

The only way to make those smaller pixels equal to the larger pixels is to downsample by a factor of two.

1479
EOS Bodies / Re: Will the next xD cameras do 4k?
« on: February 28, 2014, 04:31:04 AM »
...
Now Panasonic comes out with 4K video at 24 frames per second... still not fast enough to do anything beyond very slow moving objects

4k video at 24fps is not fast enough for ... anything?

Someone better tell Hollywood that the frame rate they've been using for decades in nearly all of their movies is too slow for motion!
Good point :)
They also have a lot more skill at movie making than I do... a LOT more...
My movie making has been recording musicians (slow), scenery while paddling (slow), and birds and a hyper kitten (very fast). 30fps is fast enough for the first two, and 120fps isn't fast enough for the second two...

Your still thinking like a photographer. When it comes to video, it's always 24fps, or 29fps, or 30fps. Those are the standard cinematic frame rates. They don't change. Doesn't matter what your filming, you always use those key frame rates. Video is quite different from stills in this respect...one of the things that is great about these lower frame rates is they are slow enough to exhibit motion blur, which is actually quite a desirable thing for cinema.

The Hobbit movies were filmed at 48fps. That lead to a lot of complaints from many movie goers. The lack of motion blur results in it being a LOT easier to spot the propishness of props, it results in movement that is too crisp, panning that is too sharp, etc. Hollywood cinematographers are going to have to discover a whole new batch of tricks to hide the fakeness of movie scenes with higher framerates. At 60fps, which is coming down the pipe, it will be even harder to conceal than at 48fps. And the stark kind of motion-without-blur will become even worse.

I think 48fps and 60fps may be a little ahead of their time. They are CERTAINLY ahead of the post-processing tools. I think a lot of the means cinematographers have to hide the fakery at 24fps is ultimately going to end up being done in post. I think motion blur, achieved by cross-blending certain parts of sequences of frames, will also ultimately be achieved in post, if higher frame rates are really the way of the future for cinema.

For anyone who isn't a professional cinematographer, however, 24, 29, and 30fps are pretty much the staples. Even if your filming birds.

Are you a cinematographer or video maker? I would be really surprised if you said yes as then you would know better than to say these things. 48/60 and more fps is required when things need to be shown in slow motion. Many times birds need to be shown in slow motion to create drama and to catch things which normal motion would not do.

Sure, if your filming slow motion. I've said as much earlier in this thread. But for standard motion video, your usually at one of the standard frame rates, because those are your playback rates. As far as slow motion goes, you can film up to 100,000 fps if you really want to...that means, technically speaking, frame rate is arbitrary. Slow motion is a special case, you usually buy a piece of equipment specifically capable of doing slow motion if your interested in slow motion.

But that's not what were talking about here. Were talking about average people "needing" 4k video to shoot average things. Your not going to be at 48 or 60 frames per second. People who would ultimately use a 750D to shoot 4k video are just going to flip it to video mode and start shooting 4k video...and that is going to be at 24fps. For the people who are a little more serious than your average person shooting average video, then they are likely to have something more capable. A 5D IV or a 1D X II, where you might actually have the option of 60fps to support some basic slow motion for cinematic video recording. However, that brings us right back around to the original argument:

Canon won't be offering that kind of 4k video support any time soon, not in their DSLRs. The 5D IV is a couple years away. The 1D X II is probably farther off than that. I suspect there will be a more cost-effective Cinema EOS model before either of those two come out with 4k video.

1480
EOS Bodies / Re: EOS 7D Mark II Announcement in Q2 of 2014 [CR1]
« on: February 28, 2014, 01:32:47 AM »
So, this is a rumor that there will soon be a rumor?

It is a discussion as to the accuracy of a rumour that there may soon be a rumour of a possible announcement that there may be a release of specifications in advance of a product release.

Translation: nobody knows


I.E. Rumormongering  :P

1481
EOS Bodies / Re: Hardware Hack for EOS Cameras Coming Soon? [CR1]
« on: February 28, 2014, 01:30:54 AM »
Hmm, new main board. That sounds like a total sensor replacement to me...Sony Exmor in a Canon body? Alternative to DIGIC as well? The thing I would be curious about is how will the camera perform overall. The 5D III is an excellent camera, and it performs well, in many cases exceptionally well, in pretty much every area. That includes IQ, even though it doesn't have the low ISO DR.

If someone slaps in a different sensor and image processor, I really wonder how that would impact the 5D III being the 5D III....

The whole thing sounds very suspicious to me.

One possibility is it's a custom firmware version with the ML hacks for expanded DR and Raw video added.

Sell it as a main board replacement for more profit, when in fact it's just a firmware update.

Phil.

Eh, I doubt that. They would get found out quick. This is the age of the social internet. If that's all they were doing, they would get CRUSHED by Twitter. They would be out of business in a week. It's got to be comething more than that, if they are doing a mainboard replacement. For a grand, it has to be something rather substantial. Taking apart a DSLR, making careful modifications, and reassembling aint cheap. Hell, to have the standard IR cut filter removed from a DSLR and replaced with one that passes 90%+ of the deep reds for astrophotography, it costs about $450! And all that is doing is replacing the built-in filter stack with a custom filter stack from Astrodon. The filter itself only costs about $150...the rest is labor cost, because it's very careful, painstaking work that requires a very skilled hand.

So, my guess is if this company actually exists and actually ends up offering this, it's far more substantial than just a firmware hack. It's new hardware. Either a new DSP, a tweaked DSP, or a new or tweaked sensor. I think new sensor, and a non-Canon sensor at that, if they are actually replacing the main board. It may not be a Sony Exmor, but there are a number of other sensors out there that offer great IQ and more DR.

1482
Landscape / Re: Deep Sky Astrophotography
« on: February 28, 2014, 01:11:49 AM »
With the low end rig, you are going to have a tough time getting the kind of image I did, not because I'm good (I'm not.) You need to very precisely align and calibrate your mount to be able to track accurately for a long time, because of the small aperture. You would need to be able to track stars for at least 10 minutes without "drift" (something you can correct for with drift alignment, a painstaking process). You really wouldn't be taking advantage of a cooled CCD there, so I really would just recommend using a DSLR. Save you some money (especially if you already have a DSLR). Use an Astronomik CLS filter with Canon DSLRs, and you can even shoot under the light polluted skies of the city.

Once you get more serious than a $400 OTA and a DSLR, you can move up the line to higher and higher grade setups. It starts getting more expensive once you get into monochrome CCD territory, because you have to use filtration. (Unless your just interested in pure monochrome imaging, some people do that.) Filters for astro are like filters for normal photography...you get what you pay for. Astrodon and Baader Planetarium make some of the best filters. At the very least, you would need LRGB filtration to use a mono CCD. If you live under light polluted skies, narrow band is the better option, as it cuts out ALL of the pollutant light, however narrow band imaging is much tougher...you still need very precisely aligned equipment, and you need to expose for at least 10 minutes, often as much as 20-30 minutes. Generally speaking, a CGE Pro or LS850 are BARELY going to get you more than 10 minutes unless you have exceptional skill at aligning. You need to move up to the high end mounts, especially those with absolute encoders, to really get the kind of tracking necessary for good narrow band imaging. Narrow band is a lot tougher to process in post as well...you have to do something called mapped color, where you map the SII, Ha, and OIII wavelengths to the red, green, and blue channels. But it isn't really just that simple, you have to make sure the images blend smoothly into each other...it's pretty advanced stuff, but the results are truly amazing.

If you move beyond 8-9.25" scopes or medium sized refractors (refractors are good, but these days generally don't have nearly the aperture of reflectors, or they do, it's just ultra costly, similar cost to the 600mm f/4 L II lens), then your really looking at a "permanent" setup. You are then either planning to build an observatory on your property, or build or rent one at a remote location like New Mexico Skies, where you can have remote computer control and high end robotic mounts (Paramount, ASA, 10Micron, Astro-Physics) under skies that are always dark, always away from light polluted cities. This is what a lot of serious amateur astrophotographers do, though...you would be surprised how many have about $20k to $30k in equipment and have built their own observatories on their land. All things considered, if your serious about normal photography, like wildlife or sports, you've probably spent about that much on your photography equipment (I know I've spent a little over $20k on my photography equipment.) So, while it sounds like a lot...it actually isn't all that much more than most people spend on their hobbies anyways (and, in many respects, a LOT cheaper than many hobbies...some people spend hundreds of grand on their "Fix up that old muscle car" hobby or their watersports hobby or whatever.) You can also kind of work your way up there as well. If you start with a really good mount, like the Astro-Physics Mach 1 or the iOptron CEM60, you have a very good mount that will last you for a very long time, and support most of the OTAs you might use (until you get up above the 10" cassegrain range...then you'll need something larger than a Mach 1).

There is another option for those who already own good normal photography equipment. The Canon L-series telephoto lenses make EXCELLENT telescopes. They rival high quality refractors like the Officina Stellare Hiper APO 152, which is a 6" (152mm) aperture just like the EF 600mm f/4 L II. The Hiper APO 152 costs about the same as well. Pretty much any Canon great white L-series telephoto can do the job, the old Mark I generation as well as the Mark II. You need to either get some custom parallax rings built to hold the lens into your mount, or get some ADM saddles and dovetail plates to bolt the tripod foot to your telescope. Along with some guiding equipment and a good midrange mount like the Orion Atlas EQ-G, and you have yourself a very high end setup capable of taking some amazing images.

The most popular lens to do this with, it seems, is the EF 400mm f/2.8 L Mark I. It's relatively cost effective, relatively long, has an ultra wide aperture so slapping on the 1.4x and 2x TCs gets you 640mm and 800mm focal lengths, which give you a good range with which to do moderately wide field astrophotography. (If you really want to use the 2x TC, it's best to go with the Mark II generation than the Mark I, but either will still do...the Mark I will just not be quite as pinpoint sharp, and will suffer from aberrations in the corners of the field.) The ADM saddle parts and necessary dovetail parts might cost around $350-$500. A basic guide scope, the Orion SSAG Magnificent Mini Autoguider, costs about $425. Along with the $1500 mount, and you have youself a pretty high grade astrograph setup. Obviously, this assumes you already have one of Canon's great white lenses...but with so many wildlife photographers around, that isn't all that unusual.

Even if you don't have a Great White lens, if all you have is a 70-200mm and a Canon 550D, you can still actually do quite a bit of astrophotography. You will need a good mount, the Orion Sirius EQ-G is a good place to start, however if you think you might eventually want to move up to a 6" or 8" scope, you should get the Orion Atlas EQ-G. You can mount the camera onto a V-type dovetail plate, which clamps into the saddle on the mount. Once you polar align the mount, you can then use the mount's hand controller and GOTO system to point your camera at anything in the night sky. You can  then either just use a normal remote shutter release and bulb mode to take exposures...and they could be very long, up to a few minutes even (without guiding, much longer with guiding). You would be blown away at what a good old 85mm or 50mm or 24mm prime can do for you on a tracking mount. Those are your ultra wide field lenses, and they capture either the whole sky, or constellation-sized regions. The 70-200mm lenses and 135mm lens are also excellent for wide field work, although not quite full-constellation size. At 200mm you can zero in on just the Orion Belt and Sword region of the Orion constellation, for example. If  you have a 400mm lens you can zero in on just the belt. If you have something like the Tamron 150-600, you can zero in on just the horse head and flame nebula region in the belt or just the Orion nebula region in the sword.

You can do a hell of a lot with just a lowly Canon DSLR, your existing lenses, and a $1000 tracking mount. At the very least, it's a place to start before you begin working your way up to that awesome $30,000 rig! :)

1483
Landscape / Re: Deep Sky Astrophotography
« on: February 28, 2014, 01:11:38 AM »
So, either lay it on me, or just shut up. Because otherwise I'm just done dealing with you. It's a waste of time.

It's good to see you are not angry with me, glad to hear that!  Yes Jrista, you are not a maniacal ego maniac whatsoever, and you are not out to get off on proving everyone wrong, and how smart you are.  You are not an immature self absorbed child whatsoever, are you?  Nor were your feelings hurt (obviously).  Since you're done dealing with me, that's fine, because I wasn't offering any deals, so we can both win on that one. 

Well, there we go! At least I got an honest, unmitigated, clear and open opinion out of you. I'm not surprised about it, either. I suspect you would say the same thing about Neuro as well. I also suspect that most people would believe your wrong on all counts, about both of us, and anyone else you might have such a similar opinion of. But wow...good to have the air cleared! Maybe we can leave the underhanded sideline insults behind us now, and move on...? (Of course, you'll always be free to dish it all out in PMs if you just, you know, feel the hankering, and really, PMs, so everyone else doesn't have to "deal", you know?)

How much of a price difference would just buying a telescope with a cooled CCD imager cost?  Couldn't you get like a 6 or 8 inch scope for like $2k to $3k, and a quite decent imager for less than $10k?  Total cost would be similar to maybe,  I don't know, a grand or two more, than your 7D and 600 ii combo.

Alright. First, I am spending my precious personal time here not because I'm some maniacal egomaniac troll who gets his LULS from proving people wrong. I spend my time writing things like this for the simple purpose of sharing my knowledge (with the honest intention of helping others expand their skills or improve their knowledge), and to correct misconceptions, debunk myths, and otherwise root out the twisted and convoluted "factoids" that many anti-fans may spew in order to trick unsuspecting readers into thinking something that is just plain and simply not true. I have said this in the past, but I'll say it again, because it's true...I really don't care what people think of me.

I care what people think, about information, the information they may be presented with and the context and other parties involved in an exchange of information, and when people misuse information to misinform and twist the facts, that bothers me. It happens a lot. We have quite a few members on this forum who just LOVE to twist and convolute the facts, either because they just despise the brand we all come here to talk about (i.e. Mikael) or because they have an agenda. THAT is why I persist in my extensively long, highly detailed posts. It isn't about me...it's really just about the facts. And that isn't for my own good...it's for the good of those who might actually take the time to read what I write. I want people to be well-informed about the facts, or educated enough to make a good judgment about subjective material when it arises (this is, after all, a rumors forum.) If you disagree, and truly think I'm wrong, and have the evidence to back up your opinion, prove it! I think I've proven myself that I'm quite capable of accepting when I'm wrong when proper evidence shows that I'm wrong. I have never claimed to be infallible (which is something an egomaniac WOULD do  ::)).



This is for anyone reading this, not just Carl:

If you are interested in getting into astro, the kind of equipment you've mentioned is pretty costly. For one, once you get into the realm of cooled CCD imagers, your into the realm of buying each piece individually. You need a mount, a scope, an imager (and all the related accessories), as well as the appropriate guiding equipment (unless you REALLY go all-in on the mount). And you need the kind of quality equipment that will allow you to take full advantage of a cooled CCD imager.

(...bleh, I'm re-stacking my image, and it's sucking up all my cpu....letters are trickling onto my screen at a rate of about 1-2 every second...)

A really low end CCD imager might cost you a few hundred bucks. A single-stage cooled CCD is going to be around a grand, however single-stage doesn't always cut it...it can't always combat ambient temperature well enough to maintain a constant temperature, which is really what it boils down to. You don't just want cold, you want constant cold. For that, you need a two-stage TEC system, and that bumps the cost up to around $3000. Once you move into the realm of cooled CCDs though, most of those are monochrome. That means you need a filter wheel. Those can cost a couple grand themselves, especially the ones with pre-filter off-axis autoguiding capabilities. The autoguider itself is likely to cost another grant. So were talking about $5000 to $7000 for a midrange 2-stage peltier-cooled CCD camera with filter ring and off-axis guider.

If you really want to go balls-to-the-walls, you can pick up either a full-frame CCD sensor (same 36x24mm size as FF DSLRs) or a large 4096x4096 square imager. These tend to run somewhere between $10k and $45k. Some of the larger square sensors use three-stage cooling with an additional watercooled option for the third stage. The sensors of the highest end models are often medium format sized. Pixel sizes can be as large as 9µm!

As for the scope, there are a hell of a lot of options. You can pick up an Astro-Tech 6" Ritchey-Chretien Astrograph for about $400. That is the same aperture diameter as my 600mm lens, however the f-ratio is f/9, rather than f/4. That is more than two stops, meaning you need exposures at least four times as long. My image above was done with 180 second (3 minute) exposures. You would need to go full 10 minute (600 second) exposures with the AT6RC. Getting longer exposures like that requires not only good equipment, but you also have to align that equipment extremely, extremely well (and it's best to use an off-axis guider (OAG).

You can get a cheap OAG like Orion's and use it with an SSAG, and you might spend less than $1000, but since were talking cooled CCD imaging, your probably in the $5000-$7000 CCD range now anyway. You really want a better OTA than the AT6RC to take full advantage of that fancy imager. There are larger scopes that will do the job. The Celestron EdgeHD 11" is one of them. It clocks in at around $3300, just for the OTA. It needs a mount capable of handling at least 40lb capacity (80lb with weights.) The Astro-Tech 12" Ritchey-Chretien Truss, a newly released truss-type cassegrain, runs for about $4500. It's the cheapest truss astrograph on the market, and uses the Ritchey-Chretien design used in all the huge multi-meter cassegrain type scopes in professional and university observatories.

You can also move to the next step up, the AT16RC Truss, which runs about $7000. Now with a scope like this, your into the realm where you can really take FULL advantage of a cooled CCD imager. The Truss design handles issues like flexure very well. It reduces weight, since you don't have a closed tube consuming materials. The open design eliminates temperature issues...as the air cools, you don't have to deal with a temperature gradient between outside and inside air. This reduces extraneous sources of tracking imperfections that affect the stability of your stars and their position on the sensor for longer exposures.

Beyond the AT16RC Truss, you move into the realm of RCOS and PlaneWave scopes. They also use the truss design, RCOS uses Ritchey-Chretien (RC) type mirror design while PlaneWave uses the Corrected Dall-Kirkham (CDK) type mirror design. These are the top two mirror designs for high end scopes, and they both have their strengths and weaknesses, however PlaneWave's CDK design seems to produce some of the best on and off-axis spots in the market. For wide-field imaging (where you don't intend to crop, rather you intend to use every square pixel of every image that comes out of the scope), where corner performance is just as critical as center performance, RCOS and PlaneWave are the best choices, as they offer some of the best off-axis performance on the market. You pay for it, however...as these scopes tend to START at around $15,000, and can be as high as $200,000.

Finally, you need a mount that will support your equipment. Working backwards from the high end, you have ASA mounts, Astro-Physics mounts, Software Bisque's Paramount, and 10Micron mounts. These all cost about $10,000 for the low end, and as much as $50,000 for the high end. They can handle scope capacities of 100lb to several hundred pounds (which is often the case with the larger RCOS and PlaneWave scopes.) ASA makes some of the most precise and accurate mounts in the world. The lowest end mount from ASA that might handle a PlaneWave is about $20,000. Their mounts have an intrinsic error rate that is less than 1" (one arcsecond), lower than any mount from any manufacturer listed. Mounts from Astro-Physics, Paramount, and 10Micron cost about the same, and offer similar performance (although most require periodic error control or PEC to be programmed and enabled first, or the addition of absolute encoders, which greatly increases cost). 10Micron mounts are a nice middle-ground. They always come with built-in absolute encoders, so they offer not only high tracking accuracy and precision, but they can also compensate for issues like wind, or can pick up exactly where they left off if there is a power loss (most other mounts must first "sync to home"). If your using an RCOS or PlaneWave, you are going to be using one of these mounts.

The next step down would be the high end of the midrange mounts. This is the Celestron CGE Pro and the Meade LX850. These mounts are not as precise as the top end mounts listed above, but they will give you good tracking accuracy, and with PEC offer precision under 2". They both offer sync to home behavior, so if your using bigger equipment (i.e. scopes larger than 9-10") that need a more "permanent" installation, they are the cheapest options that meet the criteria. They can handle scopes and other equipment weighing up to 90lb. These mounts cost about $5000. Astro-Physics also offers a $7000 mount called the Mach 1 that offers most of their high end quality and precision, however it is only capable of handling 45lb of scope and accessory weight, so it is often not an option for larger scopes. It'll handle the Celestron EdgeHD 9.25 or AT8RC well enough.

The mainstream mounts that most amateur astrophotographers use are the Celestron CGEM, Orion Sirius and Atlas, SkyWatcher EQ-6, and iOptron iEQ45 and ZEQ25 (and probably the forthcoming CEM60). These mounts cost in the range of $1000 to $3000, and usually have capacities ranging from 20lb to 60lb. They can handle most of the entry-level and midrange scopes, including things like Celestron's EdgeHD 9.25" and even EdgeHD 11", AT6RC, AT8RC, maybe AT10RC, Meade's counterparts to Celestrons EdgeHD scopes, etc. They will also handle most of the refracting scopes on the market with the exception of a few, such as Officina Stellare's larger refractors (and probably most of their reflectors.)

So, you have three major brackets of equipment that would work for cooled CCD imaging...low end, midrange, and high end. You can probably split midrange and high end into two sub brackets:

Low End (for astrophotography):

$1000 Orion Sirius EQ-G Mount
$400 Astro-Tech 6" Ritchey-Chretien OTA
$1200 Atik 420C Color CCD (cooled, ~30°C Delta-T)
$425 Orion SSAG 50mm Mini Autoguider
-------
$3,025

Lower Midrange:

$1500 Celestron CGEM or Orion Atlas EQ-G Mount
OR
$3000 iOptron CEM60
$1300 Celestron EdgeHD 8" OTA
$4300 SBIG STF-8300 Mono + 5 slot Filter Wheel (remote controllable) + LRGB color filters +  OAG (cooled ~50°C Delta-T)
--------
$7,100-$8,600

Higher Midrange:

$5000 Celestron CGE Pro or Meade LX850 Mount
$4500 Astro-Tech 12" RC Truss OTA
OR
$7000 Astro-Tech 16" RC Truss OTA
$5500 SBIG STT-8300 Mono + 7 slot Filter Wheel
$950 Astrodon LRGB Filters
$725 Astrodon OIII (Oxygen 3) 3nm Narrow Band Filter
$725 Astrodon SII (Sulfur 2) 3nm Narrow Band Filter
$725 Astrodon Ha (Hydrogen-Alpha) 5nm Narrow Band Filter
--------
$18,206 - $20,625

Lower High End:

$15000 10Micron 1000HPS or Paramount MX or Astro-Physics 1100GTO
$7000 Astro-Tech 16" RC Truss OTA
$5500 SBIG STT-8300 Mono + 7 slot Filter Wheel
$950 Astrodon LRGB Filters
$725 Astrodon OIII (Oxygen 3) 3nm Narrow Band Filter
$725 Astrodon SII (Sulfur 2) 3nm Narrow Band Filter
$725 Astrodon Ha (Hydrogen-Alpha) 5nm Narrow Band Filter
--------
$30,625

Ultra High End:

$33000 10Micron 4000HPS Mount w/ Absolute Encoders
OR
$37000 ASA DDM160 Mount
$50000 24" PlaneWave CDK OTA
$2000 Digital 10 filter Filter Wheel
$800 MoonLite CSL 2.5 inch Large Format Crayford SCT/RC Focuser w/ digital motor & accessories
$35000 Cooled Kodak KAF-16801 CCD, ~65°C Delta-T, 16mp 9µm 4096x4096 37x37mm sensor [Many manufacturers use this sensor, SBIG, FLI, etc.]
OR
$37000 FLI Cooled E2V CCD42-40 Back-Illuminated, ~65°C Delta-T, 4.2mp 13.5µm 2048x2048 28x28mm sensor
OR
$37000 FLI ProLine Kodak KAF-4301E Class 1 CCD, ~65°C Delta-T, 4.3mp 24µm 2048x2048 50x50mm sensor
$950 Astrodon LRGB Filters
$950 Astrodon OIII (Oxygen 3) 3nm Narrow Band Filter
$950 Astrodon SII (Sulfur 2) 3nm Narrow Band Filter
$950 Astrodon Ha (Hydrogen-Alpha) 5nm Narrow Band Filter
$950 Astrodon Ha 3nm Narrow Band Filter
----------
$125,550 - $131,550


1484
EOS Bodies / Re: Hardware Hack for EOS Cameras Coming Soon? [CR1]
« on: February 27, 2014, 11:11:46 PM »
Hmm, new main board. That sounds like a total sensor replacement to me...Sony Exmor in a Canon body? Alternative to DIGIC as well? The thing I would be curious about is how will the camera perform overall. The 5D III is an excellent camera, and it performs well, in many cases exceptionally well, in pretty much every area. That includes IQ, even though it doesn't have the low ISO DR.

If someone slaps in a different sensor and image processor, I really wonder how that would impact the 5D III being the 5D III....

1485
Landscape / Re: Deep Sky Astrophotography
« on: February 27, 2014, 10:36:18 PM »
Nice image, and good to see that the 7D did not completely cut out the H-alpha. H-alpha regions must be some of the harder objects to image with a non-modified dSLR.

The Astronomik CLS filter helps there. You have to expose for longer, but modern DSLR sensors don't completely cut off the deep reds. Less than 20% at H-a and even less at S-II get through, but over a long exposure duration, enough gets through that the red emissions get above the read noise floor.

... I hate to feed your maniacal ego though...
You know, you've been taking little jabs at me like that for days.
Hehe... he actually gave you a compliment, although his German way of expressing it hides it pretty well ;D

Being called a Maniacal ego maniac isn't a compliment where I come from...

... I hate to feed your maniacal ego though...

You know, you've been taking little jabs at me like that for days. I'm not really sure what set you off, but so long as you continue to slip little insults into your responses, I really have no reason to spend time responding to your questions. This isn't a thin-skin thing, either. It's simply a matter of principal. If you have a bone to pick with me, pick it, in PMs. Otherwise, just be cordial out in the public forums...that really isn't asking much.

Sorry to hurt your feelings, I will try to do better next time.

LOL. Again, my "feelings" aren't hurt. You have had a persistent issue with anyone who ever dares to contradict your opinions in any forceful manner. It isn't just me, Neuro has been on the other end of it just as much, if not more. You have a serious ego problem yourself...although yours has nothing to do with being to big, it really has to do with you being a weakling when it comes to confrontation or a conflict of opinions, especially when our presented with facts that you cannot counter because your own are FLAWED. You want to confront me, Carl? CONFRONT ME! I'm sick and tired of pussyfooting around with you. Buck up, be a man, and speak your friggin mind. Enough of this pathetic taunting from the corners. It's just plain sad.

And just to be exceptionally clear on this, because you seem to have misunderstood in the past, you and I are not friends. We never have been friends. We never will be friends. I deal with you because everyone deals with you. We all have to DEAL with you. Beyond that, your a persistent pain in the ass, always whining, always flinging sad little insults from the periphery, unable to cope when your proven wrong...at which point you resort to everything other than the cold, hard, painful facts...to mind games and button pushing and whatever else you think might somehow trip the other person up. It's very trollish, actually.

So, either lay it on me, or just shut up. Because otherwise I'm just done dealing with you. It's a waste of time.

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