So, I just got a Sigma dock for my 35 and 50 Art lenses. I was fine using them with my D3s, but I got a D800 and I found that the 50 front-focused badly with it. I used the in camera adjustment, which was fine, but the front-focusing varied a lot based on subject distance.
Today, I used the dock to carefully adjust the 50 on my D800, but now it's way off on the D3s. And because the adjustment varied based on subject distance on the 800, I can't use the in-body adjustments to fix the Backfocus I've introduced. Is there a good way around this? It's definitely disappointing to have to decide which of my bodies these lenses will work on.
Searching around, there don't seem to be a lot of people expressing this issue, but the front-focusing on the D800 seems pretty common, so I know I'm not the first to have this question. I wish the lens could store multiple camera profiles, I just assumed that it would.
I have tried the same thing. I ended up using in camera MFA for all cameras after realizing that the dock is useful for correcting focus issues within the lens such as infinity focus being off when focus at 5 feet is right on or vice versa. The way that you are using it would only be good for one camera as you have found out. You're right, there isn't much info available. This is the best info I have found.
You could use the dock to average the MFA adjustment required in each camera body. For example if the D3s required a +10 to satisfy good focusing and the D800 required a projected +30, you could set the dock to introduce a -10 which should provide an MFA setting for the D3s of 0 and a +20 for the D800. The whole thing can be a can of worms. The way I proceeded was to use MFA for 3 cameras and forget the dock FWIW.
geniousc wrote:
I have tried the same thing. I ended up using in camera MFA for all cameras after realizing that the dock is useful for correcting focus issues within the lens such as infinity focus being off when focus at 5 feet is right on or vice versa. The way that you are using it would only be good for one camera as you have found out. You're right, there isn't much info available. This is the best info I have found.
You could use the dock to average the MFA adjustment required in each camera body. For example if the D3s required a +10 to satisfy good focusing and the D800 required a projected +30, you could set the dock to introduce a -10 which should provide an MFA setting for the D3s of 0 and a +20 for the D800. The whole thing can be a can of worms. The way I proceeded was to use MFA for 3 cameras and forget the dock FWIW.
Thanks for the tip. For what it's worth, I called Sigma, and am going to try what they suggested this weekend. Essentially, they said they see the same thing: the DX family is just more consistent than the DXXX family. He said try using in camera fine tune at 2m on the 800, and see if that tightens up the grouping on the dock. I am going to give it a try and see what happens. It does make sense that if I can use in camera on the 800 to pull the furthest off saved value a little closer, then I might be able to use a combination of in camera and dock adjustments to bring both cameras in line.
FWIW, I have found Lens Alignment II to be my favorite alignment tool. I also have Focal which is ok but in my experience has not been as accurate. I really wish Sigma would put out detailed instructions on how to use this thing. Everything you read is pretty vague. Yes, let us know your results.
definitely call sigma for help. they always refer me to the same guy who seems to be the most knowledgeable person at the company. don't know who he is, but he's amazing and easy to catch on the phone.
note...the 4 adjustment distances are critical..especially for infinity focus. SET INFINITY FOCUS AT A DISTANCE OF 1 METER...not at infinity like you would think
note...the 4 adjustment distances are critical..especially for infinity focus. SET INFINITY FOCUS AT A DISTANCE OF 1 METER...not at infinity like you would think
I read that when you posted it. You know, that doesn't even make sense does it? Are you saying to set the lens focus scale at 1M and also the distance to the target from the camera focal plane or?
Please define it a bit more .
reggieb wrote:
I've been using the spyder lenscal from datacolor. Not as precise, but the 50 (at least on my D800) seems pretty darn spot on at this point.
p.1 #10 · Managing multiple bodies with Sigma dock
DontShoot wrote:
Great question. Personally, I'd just fine tune that lens to perfection on one body and just avoid using it on the other body. [/quote
The lenses generally work fine on multiple bodies by just using the in camera MFA for each body. I have 3 Art lenses and have tried to do what the op did and run into the same issue. Individually adjusted using camera MFA all are fine.
p.1 #11 · Managing multiple bodies with Sigma dock
Well, I ended up doing what Sigma suggested. I first set the D800 using the in camera adjustment at a 2m subject distance. Once done, I then used the Sigma software to adjust, and this brought the spread down to 8 (largest adjustment - smallest) versus 14 before doing that.
Then I used in camera adjustment on the D3s, and it worked really well. Everything is in much better focus now. geniousc, thanks for the tips, you might try the above method, but if yours is working for you, that's awesome, too.
p.1 #14 · Managing multiple bodies with Sigma dock
reggieb wrote:
Well, I ended up doing what Sigma suggested. I first set the D800 using the in camera adjustment at a 2m subject distance. Once done, I then used the Sigma software to adjust, and this brought the spread down to 8 (largest adjustment - smallest) versus 14 before doing that.
Then I used in camera adjustment on the D3s, and it worked really well. Everything is in much better focus now. geniousc, thanks for the tips, you might try the above method, but if yours is working for you, that's awesome, too.
Thanks again for the advice.
After reading this a second time, I am not sure I understand the Sigma methodology. Adjusting your D800 using the in camera MFA is fine. If you then adjust the lens firmware with the dock by any amount it will throw the D800 MFA adjustments off by the same amount. As an example if you ended up with a D800 camera MFA of a plus 10 and then entered a minus 10 in the dock software you end up with no changes. The dock adjustment increments are roughly, actually very close to the in camera adjustments.
In your case. with 2 camera bodies, I believe that the correct way to satisfy both cameras would be to start with the dock. Choose a dock adjustment plus or minus that will allow both camera bodies to be within the plus or minus 20 range within the two camera bodies
As an example, say your D3s required an estimated +30 and your D800 required a +10. Adjusting the dock software to a +20 would result in that now the D3s would now only require a +10 camera adjustment. The D800 would now require a -10 camera adjustment.
