Need to test my lens for sharpness

[neuroanatomist]

Its possible the ball head on my giottos tripod isnt the right thing to be using with a 5dMK2 and the canon 70-200 2.8, maybe its just not rigid enough (even with mirror lockup), yes the tripod mount is on the lens collar.

Quite possible...there's a significant difference in stability between a good ballhead and an 'okay' ballhead (and I'd put Giottos in the second category).  Also, the tripod itself may be part of the problem, for the same reason.  I was doing some focus testing a few weeks ago for some people in my camera club - in one case, two people side-by-side with 5DII + 24-105L, one with a Promaster (rebranded something else) tripod/ballhead, the other person borrowed my RRS TVC-33 + BH-55.  In Live View, the difference in stability was substantial. 

[BruinBear]

I actually had this exact same thought yesterday with my 70-200 IS II. I tried shooting the 12233 test chart printed fairly well on 17x11 paper and the corners seemed to be not as sharp as they should be. 

The only thing was shooting a chart of that size even at 200mm put the position of the lens near the MFD.  Could this cause the sides to actually be slightly OOF since its so close?

Also during checking out my lens i noticed a large piece of dust on the inside of the rear element

[mb66energy]

Examples for subtle differences in sharpness without (upper) and with minor luminance noise reduction of 2 units with DPP are attached. But sharpness isn't perhaps the right word, I would say texture fidelity is the right term: look at the speckled surfaces in the 2nd example and the glass/ceramics insulators of the 1st example.

These differences drove me mad because I thought it was an AF error of the 40D or some loose mechanical element inside lenses. The 40D involves noise red just for ISO 100 despite I set it to high iso noise reduction.

Best - Michael


First image: 40/2.8 STM
Second image: 100/2.8 Macro USM (Non-IS)

[simonbratt99]

Its possible the ball head on my giottos tripod isnt the right thing to be using with a 5dMK2 and the canon 70-200 2.8, maybe its just not rigid enough (even with mirror lockup), yes the tripod mount is on the lens collar.

Quite possible...there's a significant difference in stability between a good ballhead and an 'okay' ballhead (and I'd put Giottos in the second category).  Also, the tripod itself may be part of the problem, for the same reason.  I was doing some focus testing a few weeks ago for some people in my camera club - in one case, two people side-by-side with 5DII + 24-105L, one with a Promaster (rebranded something else) tripod/ballhead, the other person borrowed my RRS TVC-33 + BH-55.  In Live View, the difference in stability was substantial.

How is the best way to test if your tripod lens camera combo is stable enough? Maybe putting live view on with 10x to exaggerate vibration and slightly tap a tripod leg?
Assuming a totally calm day and solid ground, can the camera mechanics of taking a picture (with mirror lockup) on an 'okay' tripod and ball head, cause vibration?

I know my ball head can creep a little if not done up really tight with the 70-200 lens (let alone the 2x converter lol)

The tripod is about the right weight for carrying around for 5 hours though, its not a super light weight one.

[simonbratt99]

I just checked that ball head (Giottos MH7001) rated for up to 6kg, and the 70-200 mk2+5dmk2 is about 2.5kg so should be ok (albeit it an 'ok' brand)
http://www.giottos-tripods.co.uk/index.php?page=productpage&cat=49130e8d88135&product=49184adb70f08

The tripod MTL9351B says rated to 5kg
http://www.giottos-tripods.co.uk/index.php?page=productpage&cat=49130e801a374&product=49185f7ddd445

I think i will test it without having the tripod fully extended (when using a heavy lens)

I see your tripod is $$$$ expensive! and rated up to 23kg. Very nice just not in my price range :-)

Do you think it will help if i swap head for this one
http://www.wexphotographic.com/buy-giottos-mh1300-621-series-ii-ball-head/p1025892
Its rated at 15kg instead of my existing 6kg rated one. I dont really want to swap the tripod.

[neuroanatomist]

To test tripod stability, you can use Live View 10x and tap the legs or stomp the floor/ground.  Also, try several conditions - +/- mirror lockup, center column up, down, removed, etc. (you'll quickly find that you don't want to raise the center column!).  You can also try taping a laser pointer to the lens...

Weight ratings are good for comparing within a brand, not really across brands.  For example, I also have the RRS travel setup, the TQC-14.  It's rated for 11 kg, but I can literally suspend my own weight (82 kg) under the tripod hanging from two of the legs!

A stronger head might help a little, but I expect the difference between the two heads will be pretty minor.

[simonbratt99]

To test tripod stability, you can use Live View 10x and tap the legs or stomp the floor/ground.  Also, try several conditions - +/- mirror lockup, center column up, down, removed, etc. (you'll quickly find that you don't want to raise the center column!).  You can also try taping a laser pointer to the lens...

Weight ratings are good for comparing within a brand, not really across brands.  For example, I also have the RRS travel setup, the TQC-14.  It's rated for 11 kg, but I can literally suspend my own weight (82 kg) under the tripod hanging from two of the legs!

A stronger head might help a little, but I expect the difference between the two heads will be pretty minor.

Thats great, i have some things to work on. Ill test the tripod on concrete slabs. I have a laser pointer, i guess that will excentuate any movement, especially as my pointer goes about a mile away :-) may need an assistant.
Actually that will be great, as i will see any movement when i actually take a picture (in test conditions). I have a wireless remote that goes about 100m so i can setup the camera, walk to the lazer dot, and actuate the camera.

[Scott_McPhee]

This sharpness issue wont effect a RAW image will it?
Noise reduction isn't applied to RAW captures I believe.

I have noticed my lenses seem a little soft since I got my 5D3 - I've never got to the bottom of why though but I always shoot in RAW.

[neuroanatomist]

This sharpness issue wont effect a RAW image will it?
Noise reduction isn't applied to RAW captures I believe.

Only Long Exposure NR is applied to RAW images. 

[simonbratt99]

Im considering this as a better head to properly hold my gear (to be fitted to my giottos tripod)
http://www.wexphotographic.com/buy-3-legged-thing-airhed-0-evolution-2-black/p1533900#details

Is that going to be much better for my gear (in terms of holding it rock solid and not slipping)

[simonbratt99]

OK, just thought id update the thread.
Tested the 70-200 lens with a laser pointer taped to it. The laser dot was about 8 meters away. Tripod at full height, lens horizontal, wireless remote.
Used mirror lockup, 1st  click, dot wobbled a little, maybe 1mm-2mm
2nd  click, dot wobbled a little, maybe 1mm-2mm

Turned mirror lock off, and dot wobbled maybe 1mm-2mm
So looks like mirror lock up didnt actually help that much.

Next, closed the 2 of the 3 sections on the tripod and splade the legs out to the next setting.
With mirror lockup or not, the dot didnt move a fraction.

I guess that shows the head is not causing any movement.

Next took some test shots varying stops and up to 10 second exposures (with the tripod short and wide). Every shot looked the same (various DOF) in terms of sharpness, which was fine.

So from that i conclude the lens is fine (good news) and that there is a little flex in the tripod. How that compares to a more sturdy tripod i dont know, and how that actually affects an image 50m away im not sure.

Surely a hand held shot (with or without IS) has alot more wobble than a tripod?

[simonbratt99]

OK, ive done the last test i think i need to and thats microadjustment test
http://www.northlight-images.co.uk/article_pages/cameras/1ds3_af_micoadjustment.html

Pretty easy to do at home, took me half an hour to do 3 lenses.
As much as i wanted to find a reason to add micro adjustment, i couldn't.
Part of me wonders if ive not done it correctly as i found all three lenses (70-200 2.8, 100mm L macro, and 24-105L) to be close enough.
I didnt take any images to compare on the laptop but just tried auto focus compared to manual focus at 10x live view.
Do you think thats unusual forall  3 to need 0 adjustment?

[neuroanatomist]

OK, ive done the last test i think i need to and thats microadjustment test
http://www.northlight-images.co.uk/article_pages/cameras/1ds3_af_micoadjustment.html

I've tested the linked method, and found it had too much 'slop' for my taste - I could change the focus (or distance) quite a bit with no observable change in the moiré pattern.

[simonbratt99]

OK, ive done the last test i think i need to and thats microadjustment test
http://www.northlight-images.co.uk/article_pages/cameras/1ds3_af_micoadjustment.html

I've tested the linked method, and found it had too much 'slop' for my taste - I could change the focus (or distance) quite a bit with no observable change in the moiré pattern.

any better home suggestion?

[Normalnorm]

I am a pixel peeper for a very good reason. Stock sites are pixel peepers so i need to be.

They may be, but our company  sure gets a lot of stuff with a lack of critical focus. Good images, not perfectly sharp.