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Deryck
02-20-2010, 07:29 AM
Hi all...
now that most of the pieces have come together, ( a BESELER 45MX condensor head modified to fit a DEVERE 504 column/base, a CALUMET 4x5 view camera with a 210mm. Nikkor, and a stack of Regal ll film holders with the Ilford FP4 load ) I now consider myself basically equipped to venture into 4x5.

Having spent 30-odd years as a "medium format man", the biggest challenge for me in 4x5 (though not unexpected), is getting under the dark-cloth and trying to focus an upside down image.

My 50-some year old eye-balls just cannot turn the trick :(, so I am going to need some sort of magnifying aid to bring things into focus on the ground-glass.

My questions are these:
What are my fellow APUG'ers with like problems using as focusing aids? At what magnification? And where can I get such a one?

Thanks for your time,
Deryck

MarkL
02-20-2010, 07:38 AM
Hi Deryck,
I use strong reading glasses that you can get at a drug store. I also have a focusing loupe that comes with a string so you can wear around your neck, for more critical focusing. Can't remember the magnification of it.
Mark

Ian Grant
02-20-2010, 07:40 AM
Deryck, a lot depends on the type of screen, a plain glass screen can be the hardest to focus and so the first step might be to swap it for a Beattie/Maxwell etc screen which adds significantly to the overall brightness, sometimes equivalent to more than 3 stops. An alternative is to add a fresnel screen which adds about 2 stops brightness.

With a decent screen and good reading glasses (prescription) focussing is a lot easier, I have loupe but actually find it simpler to focus with out it, as they work best with plain glass.

You need to find what works best for you.

Ian

Krzys
02-20-2010, 07:50 AM
I find that using a loupe makes things alot brighter too.

El Gringo
02-20-2010, 08:17 AM
I started out just using an old 80mm enlarger lens as a cheap loupe, which worked pretty well to start with. Then I was lucky enough that a friend gave me a 6x lupe that he had 'free' with a camera he bought off eBay; I found this one a lot easier when focusing. Since the free loupe was quite a basic loupe the lens it used wasn't too good and it was mostly made out of plastic so I just recently picked up a Silvestri 4x loupe. This thing is great, the viewing area is wider and its an all metal loupe so I'm not worried if it gets bashed around out in the field. I'd highly recommend one.

Saying all of that I still think the biggest change has just been some experience; I'm a lot more confident at focussing now compared to 6 months ago when I first bought my LF camera. I think this added confidence in my abilities makes it a lot easier to accomplish proper focussing.

tiberiustibz
02-20-2010, 09:31 AM
When I don't have a loupe I just turn the knob back and forth looking at a single spec on the subject I want to focus on (eg, eyelashes) and try to make it as "small" (less blurry w/e) as I can by averaging the rotations gradually down to what I think is perfect focus.

Toffle
02-20-2010, 10:22 AM
I use both reading glasses and a loupe. The reading glasses are used for quick setup and sometimes they are all that is necessary for some compositions. (by the way, I have the expensive $3.99 glasses, not the Dollar-Store ones. :D )

If I'm doing anything more than really basic movements, I use the loupe to check, check and check again until I am convinced that I have either nailed every point or have split the difference accurately enough to cover with my chosen DOF. If you do a search for near-far focusing here or on the "other" forum, I'm sure you will find plenty of discussion (and maybe a few arguments :rolleyes:) as to the best way to bring your important elements into focus.

Cheers,

buzzworm
02-20-2010, 03:12 PM
There used to be made magnifiers specifically made for this available; check this website out : http://www.glennview.com/vcamacc.htm under focusing loupes about 2/3 of the way down the page. These are fairly low power (about 6x max or all you see is the texture of the ground glass) and the ones with the solid tube are much better -- they block the ambient light so you can see the image better. Omega and Schneider both made them (Schneider may still)
As a 50+ tri-focal wearer, I sympathize...

mjs
02-20-2010, 07:03 PM
I have a 4x plastic loupe I got free for helping a lady carry a box of stuff she'd bought at a photo studio auction. I asked her what she wanted for it and she said I could have it if I helped her carry her stuff out to her car.

Before that I used a really cheap loupe designed to help focus on the enlarger's easel, an old lens of about 6" focal length (turns out it's an old projection Petzval. Fun lens, used as a taking lens.) I've also used inexpensive magnifying glasses from the dollar store. Practically anything which magnifies 4x - 6x or thereabouts works ok.

Mike

jdimichele
02-27-2010, 03:44 PM
I'm currently using a Schenider 4x loupe for ground glass viewing/composing. I find that anything with less magnification doesn't work that well and magnifications greater than about 4x-6x really start getting less desirable since the grain on the ground glass is really visible as well as you are starting to view a much smaller portion of the ground glass at a time.


Cheers,
Jay
www.jasondimichele.com

Mike1234
02-27-2010, 04:05 PM
Strong reading glasses work better, IMHO. I have a set of +3 and +6. Since my myopic vision needs +1.5 for normal reading this means the 3+ provide (effectively) +1.5 for corse focusing... then the dropped own +6 (over the +3) provides approximately +7.5 for very fine focusing. This works well on my Maxwell screen... at least for me... and no hand need needed to hold the loupe means that second hand is available for camera adjustments.

jeffreyg
02-27-2010, 04:10 PM
A 7x loupe works for me

BetterSense
02-28-2010, 11:37 AM
I don't know what kind of photography you do, but if it's anything close-up, a laser pointer can be a great help. I use one nearly every time I work inside. I just put the spot on whatever I want focused and then adjust the focus until it is minimized, which is very easy to see. When it is out of focus instead of being a small point, it is a blurry circle. This is a lot easier to focus on than something smooth where you have to strain to try to see the texture pop into focus. You can put the laser spot on other things within the field and very easily see what is "equally out of focus" and so on because it's easier judging the size of the defocused laser spot than trying to judge relative amounts of blurriness.

Mike1234
02-28-2010, 12:08 PM
^^^ Yes, and for farther subjects in daylight, buy a more powerful "green" laser pointer... just not one that will catch dry leaves on fire. ;)

Ektagraphic
02-28-2010, 12:21 PM
Use a loupe and have fun with it. Like anything it will take practice and practice usually makes perfect. Welcome to large format!

Deryck
02-28-2010, 01:59 PM
Thanks for the all the welcome info on focusing on the ground-glass.

I do a lot of table-top and still life photography, so the tip from BetterSense regarding the use of a laser pointer - which I already have - really hit the spot (pun intended).

Have purchased two cheap loupes, a 4x and an 8x to see which one is better suited to my way of working.

Cheers!

Shadowtracker
04-16-2010, 10:07 AM
Hey all, I found this real helpful. I'm new to LF, using a 4x5 and don't have a focusing loupe but do have some options now that I have read all your posts. I have various magnifiers and a jewlers monocle as well as glasses. Thanks for the help.

Charles Webb
04-20-2010, 01:23 AM
I have used the Chimney View Finder from my first Hasselblad for more than 40 years. A layer of electricians tape around the bottom make it scratch free. I frankly have never found any thing that was
better.

Charlie

stevebrot
04-21-2010, 01:50 PM
I too have 50-something eyes and use +1.5 for reading. Unfortunately, that strength is inadequate for focusing the ground glass. My current solution is a pair of cheap +1.5 readers paired with +3 flip-up clip-on lenses. The combination (+4.5) allows me to see clearly at about 6" from the GG. I use a 8x loupe for fine focus, but really would be more comfortable with a 4x loupe.


Steve

Adrian Twiss
05-27-2010, 04:07 PM
Personally I use a 4x loupe that I ususally use for looking at 6x6 negatives. When I first started in LF I used a horseman 10x loupe but found I was focussing on the grain of the ground glass rather than the image. It was also a bit dark. This was on a Linhof Technica IV with standard focussing screen.

My Shen Hao has been upgraded with a fresnel ground glass usually fitted to Ebony cameras. I have no difficulty focussing with this set up. The Loupe is a Horizon model made in Russia. It has excellent optics and is very well made.