Yet Another 5D vs 7D Question

[Roger Doughty]

Just received a new 5D iii replacing my 5D ii, I also own a 7D. I love birding and will be receiving a 500 mm 4.0 ii supertele in June. With the 1.6 crop factor and a 1.4x iii extender, the effective reach on the 7D is 1,120mm. (can't use the 2x because of 5.6 f stop limit) With the firmware update on the 5D3 this spring I will be able to use my 2x converter on my 5D giving me a reach of 1,000 mm.

Here is the question: How will the quality of the pic on the 5D compare to the 7D. You will have a small crop on the 5D to reach an apples to apples comparison with the 7D pic. But there should be a lot more pixels in the 5D picture because the crop is minimal. Add in noise, AF and the rest of the benefits of a full frame vs a APS c chip and intuitively I would think the edge goes to the 5D picture. Am I smoking dope?

PS
I read all of the discussions on the 5D/7D crop considerations in April but did not see this question addressed. If I missed it, my apologies.

[Steve Campbell]

The ability to use higher ISO with the 5DIII, thus keeping shutter speed high would be one of the big advantages. I hear the 5D III can really handle higher ISO without much noise, which as the owner of a 7D, I know is not true with the 7D.

[emag]

I would think the use of teleconverters would be a significant factor also.  You have not defined what you mean by "...quality of the pic....".  Having said that, I suspect you'll like the photos w/5D3 better - but will find the 7D with that combo is no slouch either.  At the very worst, you'll have better results than you could have achieved 5 or 6 years ago.  Shoot, enjoy and find what works for you.  Hope you can wait til June.

[Jackson_Bill]

...
Here is the question: How will the quality of the pic on the 5D compare to the 7D. You will have a small crop on the 5D to reach an apples to apples comparison with the 7D pic. But there should be a lot more pixels in the 5D picture because the crop is minimal. Add in noise, AF and the rest of the benefits of a full frame vs a APS c chip and intuitively I would think the edge goes to the 5D picture.

An interesting question. According to my calculations, you would have almost the same number of pixels in either case. I assumed that you had a target that just filled the height of the 7D sensor at a focal length of 700mm and calculated the size of  that target on the 5D with a 1000 mm lens. The 7D has about 3460 pixels along the short edge and the 5D Miii image in that case would be about 3400 pixels high (note the 5D pixels are larger).
I own a 7D and the iso performance is not that good, so I agree with the comment by previous posters that you could bump the iso up on the 5D and get higher shutter speeds, which is quite important. On the other hand, both the 1.4x and the 2.0x degrade the image slightly (see the mtfs on the Canon site), with the 2x being slightly worse.
A tough call, but in my experience the higher iso would be more important.

[neuroanatomist]

Quite a while back, I formally tested the 5DII vs. 7D, and came to the conclusion that there was no significant IQ difference between an image taken with the 7D and an image taken from the same distance with the same lens (100L) on the 5DII, then cropped to the FoV of the 7D.  The only difference was that the 7D image was 18 MP, and the 5DII image was just over 8 MP - so, if 8 MP is sufficient for the intended output, there's no advantage to the APS-C.

Note that I'm comparing in a 'focal length limited' scenario - if you fill the frame with the subject on both cameras, the FF is the clear winner (compare the 7D to 5DIII or 7D to 1D X with the frame filled, i.e. closer with the FF)

More recently, I tested my 1D X vs. 7D with the same motive as yours - use with a 600 II, considering teleconverters as well (and the ability to AF at f/8 vs. f/5.6 on the 7D).  Comparing at the same focal length (bare lens or 1.4xIII), at low ISOs the 7D has a very slight advantage in terms of IQ.  But that advantage is offset by the better AF of the 1D X (shared by the 5DIII).  As you raise the ISO, the 7D is the clear loser - to me, that's a key factor, because at f/4 or f/5.6 with fast subjects, you often need pretty high ISO.  I can shoot the 1D X at ISO 6400, and it looks better than ISO 1600 on the 7D. Again, the caveat is that you have fewer MP in the final image from the FF camera if you're cropping.  But 7-8 MP is enough for decently-sized prints (16x24"), so I'm fine with fewer MP.

When you factor in the 2x vs. 1.4x TC to maintain AF, you need to crop the FF only slightly to achieve the same FoV as the 7D.  In that case, the IQ advantage of the FF is even greater and evident at lower ISOs, and that's despite the bigger optical hit with the 2x vs. the 1.4x TC (note: this is on a MkII supertele - I expect the results would be different on a lesser lens, but the MkII superteles take the 2xIII very well).

Like you, I had the 7D and 5DII combo, the former used for birds/wildlife/sports, the latter for pretty much everything else.  After getting the 1D X, I have come to the conclusion that my 7D is superfluous.  Perhaps worth keeping as a backup camera, but else mainly a paperweight.

Hope that helps...

[Random Orbits]

...

Like you, I had the 7D and 5DII combo, the former used for birds/wildlife/sports, the latter for pretty much everything else.  After getting the 1D X, I have come to the conclusion that my 7D is superfluous.  Perhaps worth keeping as a backup camera, but else mainly a paperweight.

Hope that helps...

Or convert it to IR?  I wish I had converted my old camera rather than selling it...

[J.R.]

When you factor in the 2x vs. 1.4x TC to maintain AF, you need to crop the FF only slightly to achieve the same FoV as the 7D.  In that case, the IQ advantage of the FF is even greater and evident at lower ISOs, and that's despite the bigger optical hit with the 2x vs. the 1.4x TC (note: this is on a MkII supertele - I expect the results would be different on a lesser lens, but the MkII superteles take the 2xIII very well).

Like you, I had the 7D and 5DII combo, the former used for birds/wildlife/sports, the latter for pretty much everything else.  After getting the 1D X, I have come to the conclusion that my 7D is superfluous.  Perhaps worth keeping as a backup camera, but else mainly a paperweight.

Hope that helps...

+1 for the entire post and an extra +100 for what is quoted above. The IQ and AF of the 5D3 leaves the 7D in the dust, so don't be surprised if the 7D ends up gathering the dust ... Mine did!

Anyhow, I traded my 7D yesterday ... Glad it's moved on to a new home where it will be put to use - a pretty good camera in its own right but the 5d3 is miles ahead.

[tphillips63]

I agree with the others about the 7D.  I already sold mine.  Once I got the 5D Mark III, I never used it again, well once, but I thought I had grabbed the 5D MK III, until I looked at the images and knew I had the 7D.
It was right after that episode that I sold it.  I don't miss it one little bitty bit.

[Roger Doughty]

Thanks for the valuable input! And a special shutout to neuroanatomist for his research last year that provided the basis for my query. Now I have a really cool paperweight.

[J.R.]

Thanks for the valuable input! And a special shutout to neuroanatomist for his research last year that provided the basis for my query. Now I have a really cool paperweight.

Use it well 

[serendipidy]

Posted by: Random Orbits
« on: Today at 05:13:43 AM »
"Or convert it to IR?  I wish I had converted my old camera rather than selling it..."


How does one do that?? Are there different types of IR?

[AlanF]

Like you, I had the 7D and 5DII combo, the former used for birds/wildlife/sports, the latter for pretty much everything else.  After getting the 1D X, I have come to the conclusion that my 7D is superfluous.  Perhaps worth keeping as a backup camera, but else mainly a paperweight.

Hope that helps...

I agree with what you write, applied to the 5D III vs 7D. The brilliantly consistent autofocus (same as in 1DX) is the greatest improvement, even more than the iso. But, I am keeping the 7D both as a cheap back up and as a spare camera for use by family when going out birding. My wife on her first outing with the 7D and a 400mm Sigma Tele Macro (the biggest bargain in lenses, it outperforms the 400mm L at 5th of the used price) was doing nearly as well as me with my D III and 600mm L costing nearly 10 times more.

[dtaylor]

Just received a new 5D iii replacing my 5D ii, I also own a 7D. I love birding and will be receiving a 500 mm 4.0 ii supertele in June. With the 1.6 crop factor and a 1.4x iii extender, the effective reach on the 7D is 1,120mm. (can't use the 2x because of 5.6 f stop limit) With the firmware update on the 5D3 this spring I will be able to use my 2x converter on my 5D giving me a reach of 1,000 mm.

Here is the question: How will the quality of the pic on the 5D compare to the 7D. You will have a small crop on the 5D to reach an apples to apples comparison with the 7D pic.

When the crop factor is 1.6x the 7D does record more detail, but this only becomes apparent with really big prints. This becomes very clear with really big prints and cropping >1.6x. But admittedly most people don't push that hard and never see the difference.

Your lens/teleconverter mix results in virtually no cropping of the 5D3 image at all. (10%?) At low ISO it will be a wash between the sensors after post work (USM and LCE). At high ISO the 5D3 is going to walk away. The 7D sensor has no reach advantage here.

That said, I cannot tell you how the lens/teleconverter combos will compare. 2x produces lower IQ than 1.4x, even with Canon's latest and greatest. And you lose a stop of light. That's not enough to negate the 5D3's high ISO advantage, but it might just negate the AF advantage in dim light.

Personally, I would run a quick test of the two combos. My hunch is that the 5D3/2x will win out: still better high ISO and AF, IQ the same at low ISO. But there's a big enough question mark, based on the teleconverters, that I would probably go ahead and test it to verify IQ and AF performance.

[Brymills]

If you're going to sell it, sell it quick.  IF (and I know it's a big IF) Canon release a 7D II, the market will be flooded with second hand 7D's, and the price will plummet.  I part ex'd mine for a 5D 3 just before Christmas and got a good deal on a 2 year old camera.

Compare that with the Panasonic GH2 that I bought (don't ask why, long story...) I put off selling it, the GH3 got announced and eBay was flooded with users upgrading.

(Weirdly though, I've just checked eBay and there's only 1 for sale in the UK...)

[Random Orbits]

Posted by: Random Orbits
« on: Today at 05:13:43 AM »
"Or convert it to IR?  I wish I had converted my old camera rather than selling it..."


How does one do that?? Are there different types of IR?

Yes, there are different wavelengths associated with the infrared band.  The stuff I'm seen is the IR range close to visible light.  The IR blocking filter is removed from the camera, so it won't be able to be used for the visible range anymore.  Because the camera is now sensitive to difference wavelengths, objects look different.  The sensor channels can then be mapped to different tones to create striking images...

LifePixel is one company among many that does the conversion.

http://www.lifepixel.com/