October 24, 2014, 03:04:13 PM

Show Posts

This section allows you to view all posts made by this member. Note that you can only see posts made in areas you currently have access to.

Messages - kaihp

Pages: 1 ... 4 5 [6] 7 8 ... 20
Canon EF Prime Lenses / Re: Canon EF 300mm f/2.8L IS II USM
« on: May 01, 2014, 01:16:54 AM »
Call me backwards, old fashioned or whatever you like, but I don't really trust the idea of the 61 pt auto point selection.
You're none of those things and I absolutely hate 61-pt for One-Shot AF because it always seems to select the wrong point.

OK, I'm not alone here  ;D

For AI Servo, however, you get to select the initial point, and once you place that on the subject, lock on, and begin tracking, the subject is now tracked throughout the entire AF sensor, not just the zone.

The difference between auto selection in One-Shot and manual pre-selection in AI Servo is the key here.

I will have to work on that some more, because the 61-pt auto seems to go "all over the sensor" for me, even in AI Servo - seemingly regardless of my pre-selected point.

But on to my experiences last night:
As suggested, I did a Clear All Camera Settings and Clear All Custom Functions on the body to get rid of the BIF-optimized settings that I've previously tried and set up the camera to my preferences (BBF, direct selection of AF point on the joystick, AFMA enabled, etc).

When starting to shoot, I found that the AF was doing something really weird on me: it would choose the center AF point for final focus even if I had set the AF point to a different point. After desperately trying to change settings on the fly and understand what was going on, I caved in and gave the body another Clear All Camera Settings. That fixed it. Clearly, I don't understand well enough how all those AF settings work together, and I didn't have the time to sort it out the systematically at the time.

I used AI Servo, High-Speed continuous and shooting short bursts of 2-3 shots at a time. I would vary keeping AF engaged while following the model walking down the runway to stopping/re-acquiring AF with the BBF. Same when they paused at the end of the runway.

AF selection points:
When using both Zone and 61-pt auto-selection, I found that it focused on the "wrong" points, just like mackguyver is describing. I didn't find much difference between the 5 & 9-pt expansion modes, where I had more lenience about following the model with the selected AF point, than when using a single point. No surprises here  :)

AF mode and adjustments:
With the resets, I went back to AF Mode 1, without adjustments. Later I tried to change the Focus/Shot priority from both/both to focus/focus, but since this doesn't seem to be registered in the EXIF, I am unable to distinguish between the two settings. Next time, I should shoot to a new card folder when changing modes.

I didn't spend too much time on chimping during the show, but my impression is that chimping is only good for sorting out the glaring misses: I have to get the pictures up on my computer monitor at 50% or 100% to sort out the shots where the focus is almost there vs the shots where the focus is just nailed.

Looking at several series of shots (each model walking down the runway), it looks like that the tracking speed / snap-on speed is not up to my expectations. This could be the start of a longer investigation, since chimping doesn't seem to be good enough to tell the difference.

Canon EF Prime Lenses / Re: Canon EF 300mm f/2.8L IS II USM
« on: April 29, 2014, 08:36:35 PM »
I would go with zone over 61 pt auto
If he was shooting with a wider lens, I would agree, but given that he's using the 300mm, he's going to fill the frame pretty quickly and zone AF might be a bit limiting from a compositional standpoint.

Call me backwards, old fashioned or whatever you like, but I don't really trust the idea of the 61 pt auto point selection. But as I've said, I'll give the 1/5/9/61pt modes the test tonight.

Zone AF should be fine, as I can just put the top third in as zone (I'm shooting exclusively in portrait mode at this venue with the 300mm) and this aligns up with the upper body/face of the models as they walk down the runway.

I'll check in on ideas here before heading out tonight.

EOS Bodies / Re: New Sensor Technology Coming From Canon? [CR1]
« on: April 29, 2014, 08:25:41 PM »
I think your cost estimate of $1000 for a FF sensor is way off....

No doubt, thus the mention of the per wafer cost being a WAG (wild-asset guess).  It was a relative example, the absolute numbers didn't matter.

Jon's point about different wafer sizes changes the the relative numbers, of course, but the main point remains - there are possible scenarios where a process change could decrease production costs for FF sensors but not for APS-C sensors, because of the differential effect of random blemishes with FF sensors that are 2.6 times the size of APS-C sensors.

I would guess at a wafer cost is in the range of $2000, given the technology nodes in play (180-500nm)
For the differences in cost structure, see my previous explanation.

Lenses / Re: Canon's f/1.2's: What is really going on?
« on: April 29, 2014, 08:14:02 PM »
I worry about you guys sometimes. I have lenses I must have changed thousands of times and there is no discernible wear.


'Excessive wear on the mounts'??  Even the plastic bayonet mounts on (relatively) low cost lenses are pretty durable, although they'll wear eventually.  The metal bayonet mounts of bodies and most lenses will not wear appreciably even with many years of heavy use.


Plus, the bayonets are replaceable.

EOS Bodies / Re: New Sensor Technology Coming From Canon? [CR1]
« on: April 29, 2014, 11:38:12 AM »
1. What yield improvement were you thinking of that is of no benefit to APS-C sized sensors?

2. If it is of benefit to APS-C sized sensors, why apply it only to full frame sensors? Surely you apply the technology that improves yield to the production line that has the highest production levels (i.e. APS-C), not the one with the lowest?


I'm not sure why you are asking about FF vs APS-C sized sensors here, as my comment was meant truly generally and did not speak of sensor size.

Lenses / Re: Canon's f/1.2's: What is really going on?
« on: April 29, 2014, 11:35:23 AM »
she said she had tried it and decided it just wasn't reliable enough for what she was doing with a 50mm.

It should be noted that the f/1.2L has a focus-shift when shooting in f/1.4 to f/4 range. This is a deliberate design choice, but it can really catch people out.

See this excellent explanation by Neuro.

Lenses / Re: Bought the 300mm 2.8 ii and think its huge
« on: April 29, 2014, 10:41:57 AM »
That could well be your problem, BIF in good light, as per cervantes settings, are about as far away from a tuned AF set up as you can get for a model runway shoot in poorer light.

The beauty and problem with modern AF is it is so customisable that settings for one subject and situation will be very bad for another. The "twitchiness" he is inducing in his custom settings do not make so much sense for runway shooting. The Accel/Deccel setting isn't appropriate for runways, the model's speed is comparatively uniform, and the Tracking Sensitivity is the opposite of what makes sense for runways.

I'd reset to factory and work methodically from there, indeed I'd expect factory to give you a much higher keeper rate than the 30% you are getting.

Good points and I totally agree on the customizability can be a trapdoor to problems. I've given the body a Factory Reset + Custom Functions Reset, and will go out tomorrow evening to give it a new try.

I think the automatic selection AF vs Zone AF mode setting (p 74 in the manual) have been messing with me, as it seemed to auto-select the AF points, despite I had selected a single AF point.

Thanks to PBD as well as mackguyver and Menace over in the 300mm thread for suggestions. I'll keep you posted on my findings.

I'll try the 61-point "full auto" selection and the manual 1/5/9-point AF modes for comparison.

EOS Bodies / Re: New Sensor Technology Coming From Canon? [CR1]
« on: April 29, 2014, 10:28:30 AM »
Thus either this rumor is a hoax (why would Canon not want to reduce the cost of sensors made for the top end?)...

Can I flip this around: why would the top end be the priority for reducing production costs? Surely the margins are tighter at the bottom?

I believe that you're thinking it wrong: ANY reduced manufacturing costs goes straight to the bottom line.

Sure, the lower end has a higher volume, but sometimes it is easier to reduce costs at the high end simply because people didn't bother too much about cost, with the argument that "it's high end, so our focus is quality, not cost", which ends up in a circular argument resulting in high cost.

Believe me, I speak from experience (sigh).

Canon General / Re: Best Backup Strategy?
« on: April 29, 2014, 05:08:16 AM »
http://www.filetransporter.com/ might be an option for you, if you want offsite backups. As for backup crashing during the copying, you need to use dedicated backup software that notice such problems and react on the next backup cycle.

Lenses / Re: Bought the 300mm 2.8 ii and think its huge
« on: April 28, 2014, 11:17:30 AM »
For the first shot, full length with the model walking, I'd use a pre chosen single point in Servo, just select the top middle point (or the next one around the edge if possible) and crop slightly to give better framing in post, often you can batch process the crop too. For the turn and half-profile shot the same AF setting will work, but I might be tempted, because I am a One Shot AF fan, to toggle to One Shot, you can program the four black buttons on the lens to do this.

Just don't get mixed up with trying to move focus points, the models move fast and if you lose one you won't have time for the AF to regain them and get your shot, choose one and stick with it. If you look at almost any runway series from any shooter they will all be shot with the same framing and point of focus. This not only makes it easier for the photographer but it gives viewers a much clearer comparison of the look the designers have created. If the publisher wants something more dynamic then the designers can crop and rotate etc to give that look.

Aye, this is very close to what I did. I used a (semi)fixed focus point (played around with the top/2nd-top row points), and then panned/changed composition as they walked the runway. I used the AI servo mode, though, attached to the shutter button. I previously tried some of cervantes recommended settings, so I may have been fouling up the AF settings.

Canon EF Prime Lenses / Re: Canon EF 300mm f/2.8L IS II USM
« on: April 28, 2014, 10:53:33 AM »
I spent the last three evenings practising this lens on the fashion shows in the local mall (they run all week).

Still trying to get to understand how to set up the 5D3 AF system as I can't get it to focus consistently - these models aren't exactly moving like a Peregrine falcon in full dive, and I'm not even getting a keeper rate over 30%.

5D MK III Sample Images / Re: 5D MK III Images
« on: April 28, 2014, 10:37:30 AM »
I took the 300mm f/2.8L II to a fashion show in the local mall to practice how it worked with the 5D3.

1/400 sec, f/3.2, ISO 400, uncropped. (yes, I accidentally bumped the back wheel at f/3.2 instead of f/2.8).
WB is adjusted due to horrible lightning.

Lenses / Re: Bought the 300mm 2.8 ii and think its huge
« on: April 28, 2014, 10:25:29 AM »
It was a wee bit too long for the distance (the guy next to me shot with a 200/2L), but I think the focal length  turned out very well: full body at the start of the catwalk, turning to half-profile size at the end of the catwalk.

Now, the only problem left is the idiot operating the buttons and setting cannot seem to find good AF settings that give consistent focus every shot (this must be the photographers version of "a classic case of PEBKAC").

5D3, 300mm f/2.8L II, ISO 400, 1/400sec, f/2.8 (un-cropped).

Photography Technique / Re: Advice for trip to Western USA
« on: April 09, 2014, 06:34:01 AM »
Through Vegas to Zion (I'd recommend swinging through Valley of Fire just north of Vegas)
Scenic byway 12 on the way to Capitol Reef, possible quick stops at Devil's Garden (not to be confused with the Devil's Garden in Arches) & Goblin Valley.
Canyonlands & Arches
Monument Valley
Page (Upper & Lower Antelope Canyon; you'll be able to see the popular beams, but I recommend the more expensive photography tours if you go; Horseshoe Bend).
Grand Canyon

Based on Cali_PH's recommendations, I basically did this tour (flying in/out of LAX) back in October 2012, in 8-9 days. But there was quite a bit of driving involved, especially from/to LA to the Utah/Arizona area, as well as between Capitol Reef and Arches/Canyonlands NP.

Oh, I also stopped at the Natural Bridges park :)

Software & Accessories / Re: External AF assist light?
« on: April 08, 2014, 02:50:08 AM »
Yongnuo's YN-E3-RT has built-in focus-assist beam, and is the size of the Canon ST-E3-RT. Might just suit your bill, and give RT access to 600EX-RT's to boot.

Pages: 1 ... 4 5 [6] 7 8 ... 20