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08-22-2012, 01:02 PM   #1
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HELP PLEASE 300mm lenses

I just got the DA* 300mm f/4 SDM.
So far, shootng at f/8 at very white birds (egrets and mute swams) one to two stops under exposed, I think I detect a bit of softness compared to my FA* 300mm f/4.5 shooting the same subjects, same light, at the same exposures. (I know the FA* copy is probably one of the sharpest lenses ever, but I did not expect these old eyes to be able to discern differences in sharpness)
Is this my imagination? Or, is the new lens not quite as sharp as the old one?
I LOVE everything else about the new lens. SDM is quick, quiet, and, I hope accurate.
Tripod collar is heaven sent.
Filter adjustment window in the lens hood, ditto.
I would very much appreciate any input.
Thanks.
Jack

08-22-2012, 01:18 PM   #2
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What metering are you using,

Note that the metering, if spot or the bird fills a large portion of the scene will attempt to make the white appear grey (about 2 stops under exposed) that is how the metering works.

as for sharpness, the da300/4 should be just as sharp, perhapos you need to tune FF/BF
08-22-2012, 01:21 PM   #3
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The usual responses will include:
(1) please post sample pics with exif and
(2) have you confirmed the focus is adjusted properly with a chart or something just so any systemic issue would pop up?

Plenty of help in the forum.
08-22-2012, 01:48 PM   #4
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Thanks George. Minus one or two stops--it does not seem to make a difference. I will look into tunig the "FF/BF". You answered the main question though. (One of the reasons I am so concerned is that the box came already opened and "dented" on its top. The shipping carton was fine.)
Jack

08-22-2012, 01:53 PM   #5
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Thanks Lee.
I will try to post at least one from the FA* and one from the DA* as soon as I figure out how.
I have not used a chart.
As much as I like the lens, I am thinking of returning it and trying another copy.
Do you agree that the DA* should be at least as sharp as the FA*? (At least to the naked eye?)
Thanks again.
Jack
08-22-2012, 01:59 PM   #6
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If you don't want to go through the chart tests, you can focus with the live view!
08-22-2012, 02:14 PM   #7
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Thanks Zav.
But to me, at least in the view finder, focus looks fine.
I am going to post a few images in a minute.
Jack
08-22-2012, 02:19 PM   #8
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Lee--
If I can do it, here are three versions of the same RAW image. The first was opened in Elements 10 and saven untouched as a max jpg. The second is cropped, fill light at 50. The third is cropped and "auto" clicked in Elements.
Can't do it.
I will try to put the images elsewhere on this site later.
Thanks for your help.
Jack
PS
I can email them to you--let me know.
J.

08-22-2012, 02:19 PM   #9
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QuoteOriginally posted by pntxjack Quote
Thanks Lee.
I will try to post at least one from the FA* and one from the DA* as soon as I figure out how.
I have not used a chart.
As much as I like the lens, I am thinking of returning it and trying another copy.
Do you agree that the DA* should be at least as sharp as the FA*? (At least to the naked eye?)
Thanks again.
Jack
My back door is only 30m from where Great White Egrets chow down on fish constantly this time of year. Thus I have thousands of Egret shots with my da*300, both with and w/o the 1.7x AF teleconverter. Yes, a bright white egret in the sun can be a tough exposure with dark mud or trees in the background. When close, I often just switch to spot mode metering adjust it UP 1/3-2/3 stops exposure so I get white, not grey as Lowell noted. If the bird is in a fixed position, like standing on a branch over the water, I will quickly trial and error to the best settings then go to Manual and leave it until a cloud comes or it flys off. So long story short, its way too easy to overexpose and loose the detail. Thats why i asked for a sample to make sure your definition of "soft" was not my words for "blown out". I have been shooting the same spots with the da*300, a*400/2.8, and sigma 500/4.5 and can state there is nothing in the design of your lens to prevent you from having great detail. So if getting the exposure right and the BF/FF right does not do it then we have covered the typical and need to look at the complicated.

As far as a sample, you can learn how to upload and embed in your thread or link to your Flickr, Picassa or whatever you use. You know what we are looking for; is ANYTHING in focus? if so is it in front or behind the subject and then figure if you just missed the bird or the lens is out of adjustment. If ONLY the bird looks soft to your but the grass or other details around it look sharp I really expect it to be an exposure issue. Dont forget to include with your sample, or type the main settings in the thread, EXIF info.

Good luck. Lets fix it before the Menhaden all move back out to the Ocean and Egrets are less fun to shoot.
08-22-2012, 02:40 PM   #10
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Hi Lee-
I have just posted three versions of the same image in my album on this site. I don't know how to direct you there.
The description in the intro is reversed.
The descriptions that accompany each image are accurate.
Thanks.
Jack
08-22-2012, 03:24 PM   #11
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Hi Jack
I just had a quick look and see that you have the EV -1 on spot metering, I believe the suggestion was to go the other way to +1/3 - +2/3. They looked sharp enough but they are at f8. I would expect the DA to equal if not better than the FA, so definately check the micro AF adjust - in the correct fashion. It is amazing what a difference critical sharpness makes especially with long lenses.
08-22-2012, 03:44 PM   #12
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Thanks DRE--
I may be very confused. I shoot egrets and mute swans at minus one stop at a minimum, sometimes up to minus two.
My reasoning is that a "normal" exposure or plus any stops (or fractions thereof) would give me completely blown out detail in the feathers.
We may be miscommunicating.
If we are not miscommunicating, first thing tomorrow I will try the plus exposure. If THAT works, I have 10,000 or more mis-exposed images. (But tons of detail in lots of feathers.
Stay tuned.
Jack
08-22-2012, 04:04 PM   #13
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QuoteOriginally posted by pntxjack Quote
shootng at f/8 at very white birds (egrets and mute swams) one to two stops under exposed, I think I detect a bit of softness compared to my FA* 300mm
Re the exposure issue, I always shoot centre-weighted, rather than spot, when using the DA* 300 and other long tele for birds. Spot is too narrow and often causes me exposure problems.

As to the sharpness issues, it is impossible to judge sharpness from the photos you posted - they are simply too dark. But personally I find the lens sharp enough even wide open (albeit I rarely shoot wide-open since I always need more DOF).

Also: 1/5000, f8, ISO 200 - that place must be bright!
08-22-2012, 04:14 PM   #14
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Thanks rawr--
Shot between 7 and 8 this morning, PDT.
The sun had been up for a while.
It IS bright here. Plus the bird is VERY bright and the sun hitting the critter from behind and to the right of me.
08-22-2012, 04:44 PM   #15
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Yes, agree with the centre weighted @ ev0 being more consistant for longer lenses.

Jack you might have to get up earlier
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