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dentkimterry
24-Nov-2015, 17:24
I have just started to use my De Vere 5108 for the first time. I have dealt with 4x5 and 5x7 in the past but this is like starting all over. Other negs I have never had problems focusing on the grain. Easy. With the 8x10 I can't seem to do this. I'm just not sure of my focusing. I have printed a few and they turned out alright, perhaps because to the small aperture used on the enlarger lens. I have a Micro Sight III and a Magnasight which seems to work the best. Any tips friends?

LabRat
24-Nov-2015, 19:32
Here's a handy little tidbit about focusing;

When a lens is in focus, it is not only sharp, it has maximum contrast, color saturation, separation, etc... With enlarging, you can find a major tone step, and focus until there is maximum contrast between the dark and light area, and focus until the dark, dense area (highlights) are darkest, and the clear areas are bright/clear...

Try different f-stops and see if one is easier to focus with... And some focusing magnifiers are not so good, or very out of alignment... Have you focused the eyepiece to the crosshair inside to adjust to your own vision??? (And this will change if you wear glasses, and put them on or take them off...)

You might not see the grain, but with the lens wide open, sometimes the image edges will have a slight "sparkle" or other effect when focused with some lenses/enlargers/materials... Spend some practice time and some test strips and try to nail it wide open... You will eventually find some "marker" of a visual clue when in focus...

The above theory works on a camera GG also... Often you can focus until the colors are most saturated/contrasty/"pops"/more of a tone step, etc... Usually easier than finding something small with fine detail to squint and focus on...

Steve K

dentkimterry
24-Nov-2015, 19:40
Thanks for the tips Steve. I figured it out I think. I have never tried making prints this large. I had the focusing magnifier on the edge of the print. Moving to the center made all the difference. Seeing the grain was easy. Sometimes it's the simplest things! Thanks again, Terry

LabRat
24-Nov-2015, 19:51
Place the magnifier about 1/3 to 1/2 the distance off center, as this is the "hyperfocal" focusing point, as there is a minor difference between the distance on-axis, and the edges... (Most lenses are corrected for it, but....)

Good Luck!!!

Steve K

ic-racer
24-Nov-2015, 20:21
I had the focusing magnifier on the edge of the print.

What lens are you using. A 300mm should be just as sharp at the corners as the center even when focusing at f5.6. If its not sharp with the magnifier, it won't be sharp in the print.

Daniel Stone
24-Nov-2015, 22:20
Are you using a glass carrier?

dentkimterry
25-Nov-2015, 04:50
Lens is 240mm Componon S. I am using a glass carrier.

Luis-F-S
25-Nov-2015, 07:05
Check your alignment; if you have any issues with that, let me know I can walk you through it. The initial front/back is done with the baseboard, alighment between the negative and lens stage can sometimes be a bit tricky. L

dentkimterry
25-Nov-2015, 16:32
I did have alignment issues. The mount for the baseboard is not exactly square with the column. Started over plumbing the column. then re-adjusted the baseboard. A level on the column, baseboard, negative stage and lens mount all jive now. I can now focus anywhere on the image!. Thanks for your help!
Luis, how do you adjust the alignment between the negative and lens stages? The manual is not very clear.

It seems to me that this enlarger should have a bracket off the column to the wall. Anyone have experience with this?

dentkimterry
25-Nov-2015, 19:41
Just figured out something else. My easel doesn't sit level. Little high on one side. Have to try and shim the other side I guess.

ic-racer
25-Nov-2015, 21:24
Lens is 240mm Componon S. I am using a glass carrier.

Ok, yes that is blurry at the corners of 8x10. Prints seem to be OK, but I almost never use mine, I use the 300mm instead. Such a dramatic difference with a 300mm. Under the magnifier the corners are tack sharp even at 5.6.

dentkimterry
26-Nov-2015, 06:38
I got the 240 because I'm height challenged where my darkroom is. I think I'll look for a 300 though. I can always lower the baseboard. Anybody have one?

Luis-F-S
26-Nov-2015, 13:26
Luis, how do you adjust the alignment between the negative and lens stages? The manual is not very clear.

It seems to me that this enlarger should have a bracket off the column to the wall. Anyone have experience with this?
Not very stable without a wall bracket. I'll post some photos Monday when I get home of the alignment. The easel can be a bigger issue than the baseboard. L

Dave Ogle
27-Nov-2015, 08:20
I am just getting into enlarging 8x10 negatives on my Chromega F. glass negative carrier and a Rodenstock Graphigon 240mm f 11 lens. using an Omega grain focus. I also found it hard to focus. luckily a few of negs had a sharp line in the shot and could focus on that. others were alittle harder. A grain focus with higher magnification would be great. So far so good. next printing session plan on making some more detailed test strips for different filtrations.
Dave O

Greg Davis
27-Nov-2015, 08:47
When I set up my 5108 I leveled the base on he floor, then leveled the top half as I attached to the wall. Then I leveled the baseboard in both directions. With a laser aligner I leveled both the lens and negative stages side to side and front to back. There are set screws that allow front to back adjustment for both stages, and for side to side you use the tilting feature. If you are using a lot of tilt or the detents are way off you can adjust where the detent is using Allen wrenches and patience. I keep meaning to make a video of the whole process, but haven't got to it yet.

Luis-F-S
27-Nov-2015, 10:45
I got the 240 because I'm height challenged where my darkroom is. I think I'll look for a 300 though. I can always lower the baseboard. Anybody have one?

You don't need a 300. I had one n sold it. Get a 210 instead!

mdarnton
27-Nov-2015, 16:24
I don't have one, but isn't the MicroSight III an aerial image device? That is, rather than a ground glass it has a retical target of some type, crosshairs or a circle, printed on clear glass? Most people try to put their eye focused on the retical and keep it there while focusing the image, but there's another way to do it.

The image can look in focus even if it's not if you let your eye dwell on it and not the retical, which may be why you're confused, but in that case the focused image and retical will be different distances away. The way to use such a retical is do your best guess in focusing, and then wobble your eye back and forth. If the focused image is spot on in the same plane as the retical, thus in focus, it won't move. If it's ahead or behind of the retical, it will move back and forth relative to the retical when you move your view through the eyepiece, because they won't be at the same distance.

This may be hard to understand, but it's easy to see. Simply focus until moving your head back and forth doesn't cause the image to move relative to the retical, and you're done---you can just forget the technical discussion above if you want. :-)

dentkimterry
27-Nov-2015, 18:46
Thanks for that tip mdarnton. The MircoSight lll is an enlarger grain focuser. I looked the instructions up online and now know how to correctly use it. There is a reticle inside that you focus on with the diopter correction built in. Once focused on that it is used to focus on the grain. I didn't have the diopter set correctly for my eyesight so everything was off. It is all coming together for me with the help of you forum friends. I thank you.

tgtaylor
28-Nov-2015, 10:09
This makes adjusting the lens stage a snap: http://www.bhphotovideo.com/c/product/15669-REG/Delta_13310_Bes_Align_4x4_Adjustable_Lens.html

Thomas

SpeedGraphicMan
30-Nov-2015, 11:12
You can also replace your negative with a very fine plastic window screen and focus that way.