Qestions about 14in Artar image quality

[bvaughn4]

Hi all, relatively new ~1yr to LF I seem to be having trouble getting a sharp image in the GG of my 8x10 with my 14in Red Dot Artar. Is it possible that at some time in the past the lens cells have been removed for cleaning and reinstalled in the incorrect orientation? If so is there any way for me to tell the correct placement or do I need to send it somewhere for a check-up? Recommended shops?

Thanks
Bill

[Dan Fromm]

It is a dialyte. Elements should be () )( | )( (), where | is the diaphragm. I could be mistaken, but I think scrambling them is difficult.

[Chauncey Walden]

The first Artar I came across years ago had me wondering how they got such a good reputation. Figuring something was amiss I found a lens diagram and, sure enough, an element was reversed. It is a symmetrical lens so both halves should be the same and IIRC it was one of the outer elements that was reversed and that the stronger curve should be to the outside.

[Leigh]

The Red Dot Artar is a process lens, optimized for 1:1 reproduction and similar close work. I don't know how it will perform at long range.

It's always possible that somebody disassembled it to mount on a lensboard and lost the shims to set the cell spacing. Shims are not always used, but when present are definitely required. Re-assembling the lens without them will result in poor performance.

Proper adjustment of a lens of this length requires a very large collimator. I have a 48" that would work, but that's really too short for a 14" lens. If you suspect an optical problem it needs to go to a shop that has the proper equipment.

- Leigh

[Bob McCarthy]

Does a 14 inch artar cover 8x10 with sharpness to the edges, I thought not.

My G Claron does, but my 19 inch Artar is very sharp in trhe center but significant movement shows soft outer image circle.

bob

[bvaughn4]

Thanks for the information. I'll see if I can take it apart and see how it looks relative to the description provided. It's hard to tell if it is sharp to the edges, but looks like it covers with no movements.

[Jim Galli]

14" is not an 8X10 lens. You'll be soft on the edges and movements will compound that problem. 16" is a good number for 8X10 I think.

G'luck.

[bvaughn4]

I better keep an eye on the For Sale section...

[Michael Jones]

14" is not an 8X10 lens. You'll be soft on the edges and movements will compound that problem. 16" is a good number for 8X10 I think.

G'luck.

Gee, I used a 12" & 14" RD Artar at infinity for years on 8x10 and never had any issues. 16 1/2" was for my 8x20 with the same results.


Mike

[MIke Sherck]

Gee, I used a 12" & 14" RD Artar at infinity for years on 8x10 and never had any issues. 16 1/2" was for my 8x20 with the same results.


Mike

I also used a 14" RD Artar on 8x10 (on a monorail!) and never ran out of movements or had noticeably soft corners. These days I use a 16 1/2" RD Artar in an Ilex #4 and am very happy with it.

Mike