Menu
What's new
The GetDPI Photography Forum

Great to see you here. Join our insightful photographic forum today and start tapping into a huge wealth of photographic knowledge. Completing our simple registration process will allow you to gain access to exclusive content, add your own topics and posts, share your work and connect with other members through your own private inbox! And don’t forget to say hi!

Has anyone used the 23 Digaron with the IQ4?

D

Dadbod

New member
I'm having to move the focus ring all the way to its very max (past infinity) to achieve the sharpest landscapes. I don't recall having to do this with the IQ3. Has anyone found the same to be true?

Thank you,
 
O

onasj

Active member
It could just be that your IQ4 back requires a bit different focusing adjustment (shim) than your IQ3 back did.

I haven't noticed an IQ3 vs IQ4 difference for my lenses, but I can't say I ran any rigorous tests at infinity.
 
E

Eric Mansour

Member
I’ve definitely noticed a difference in sharpness at formerly hyperfocal witness marks. I’ll experiment further as to where it is now. Glad you pointed this out.
 
P

Paul2660

Well-known member
I can’t speak to the 23mm.

I have the 32 and RM3DI.

I had a set range for the 32 on my IQ260. When I received my IQ3100 I had to get Rod Klukas to adjust the helical to focus negatively around 2. No change to camera or lens. With the IQ4 I am back to positive values. Very similar to what the IQ 260 was. I assume there might be slight tolerance differences in sensor depth but very slight as the movements I describe on a Arca helical are very small

Paul C
 
D

Dadbod

New member
dougpeterson said:
If you have to focus past infinity then your infinity is wrong :).
Click to expand...

Doug, I hear you bro. But I really am at the max that the focus ring will allow. Foreground is tack, mid ground is tack and the background is very close but doesn't seem quite as sharp as the IQ3. Anyway man, if you can suggest anything that would be RAD!!


Thanks a ton!!
 
D

Dadbod

New member
Paul2660 said:
I can’t speak to the 23mm.

I have the 32 and RM3DI.

I had a set range for the 32 on my IQ260. When I received my IQ3100 I had to get Rod Klukas to adjust the helical to focus negatively around 2. No change to camera or lens. With the IQ4 I am back to positive values. Very similar to what the IQ 260 was. I assume there might be slight tolerance differences in sensor depth but very slight as the movements I describe on a Arca helical are very small

Paul C
Click to expand...
Paul, thanks man, this is super helpful. I'll let you know if I figure it out.
 
P

Paul2660

Well-known member
Back in the heyday of the P45+ Joseph Holmes wrote a lot about a similar problem. Where sensors were either not evenly placed or had spacing issues. He worked with several other pros all using the Mamiya camera and P45 + and each seemed to have slightly different spacing.

I don’t know if his blog is still up but he did a lot of work with P1 to finally get a back that had perfect alignment.

Paul C
 
D

Dadbod

New member
onasj said:
It could just be that your IQ4 back requires a bit different focusing adjustment (shim) than your IQ3 back did.

I haven't noticed an IQ3 vs IQ4 difference for my lenses, but I can't say I ran any rigorous tests at infinity.
Click to expand...

Onasj, thank you for the suggestion. I will look into it for sure.

Do you have the 23HR? If so, what camera are you using?

Thank you,

Forrest
 
V

vjbelle

Well-known member
Besides the adjustable shims the lens stop is also adjustable for infinity setting. The lens you have may be very slightly out of adjustment but, for me, that would be of no concern. I would recommend that you shim for whatever lens you have that can't reach infinity and shim so that you reach beyond infinity. You already have extremely accurate live view ability on the Phase back and 'THAT' should be your standard for focus. Setting the entire system to focus beyond infinity allows you to easily see when you are in focus at infinity or whatever your far distance is. This is how I have always approached this since the 3100.....

Hope this helps.....

Victor
 
V

vjbelle

Well-known member
If you do plan to adjust the lens stop - which is relatively easy - don't lose any screws. I remember toiling with all of that when I had my 180 but those days are behind me. Regardless I would not fool around with any of that and adjust shims so that you can focus beyond infinity with all lenses and rely on the excellent LCD at 100% pixels for perfect focus.

Victor
 
D

Dadbod

New member
vjbelle said:
If you do plan to adjust the lens stop - which is relatively easy - don't lose any screws. I remember toiling with all of that when I had my 180 but those days are behind me. Regardless I would not fool around with any of that and adjust shims so that you can focus beyond infinity with all lenses and rely on the excellent LCD at 100% pixels for perfect focus.

Victor
Click to expand...
Thank you Victor, I'm going to try.
 
GrahamWelland

GrahamWelland

Subscriber & Workshop Member
Did you buy it new? If there’s been one concern it’s the shims ... and also the decentering if you jolt the lens like the 32HR.

I had a beautiful Alpa mount 23HR that would loosen the front element and behind that was a stack of shims. I never lost or pinched one but it always worried me.
 
D

Dadbod

New member
GrahamWelland said:
Did you buy it new? If there’s been one concern it’s the shims ... and also the decentering if you jolt the lens like the 32HR.

I had a beautiful Alpa mount 23HR that would loosen the front element and behind that was a stack of shims. I never lost or pinched one but it always worried me.
Click to expand...

Thanks Graham, I did buy it new from Cambo. I think the lens is pretty dialed. More than likely i’ll just have the lens adjusted a bit.

I appreciate the post.
 
You must log in or register to reply here.
Top