Manual focus astro-scoping for those with eyesight problems (1 Viewer)

[JGobeil]

I decided to start this thread realizing I'm not the only one having eyesight problems. Maybe we can help each other.

I developed eyesight problems with age and, what makes it worse in my mind, is that my eyesight used to be better than 20/20 (no kidding).

Age (going on 70 now...) and diabetes force me to wear glasses for close focusing, up to about 5 meters. I wear progressive focus glasses and this works quite well in regular daily use - manual focus photography is another story.

Focusing using the LCD with my glasses works fine but is not an option for birding because the LCD gets washed out by the strong light. Unfortunately, we need strong light with those high f/ scopes at high shutter speeds.

Using the viewfinder with glasses works ok using auto focus: I can see and change the settings, compose and take the shot on a clear focused image. Unfortunately, the progressive glasses bring in an insidious problem: they allow me to adjust my eyesight to get clear focus in the viewfinder on objects that are NOT QUITE in focus BUT CLOSE. This is done instinctly without even realizing it. The result is that I cannot rely on glasses to focus accurately using the viewfinder - the focus looks good in the viewfinder but the results are not that great when viewing the photos on the computer.

I can use the viewfinder without glasses, adjusting the diopter adjustment dial to get a clear image on a properly auto-focused image with the 100-300mm lens on the OM-D. Unfortunately, this does not really work that well for manual focus... I discussed this recently with an ophtalmologist and he explained that my eyesight changes according to fatigue, the time of day, light levels and my blood sugar content. Granted, it does not change much but it seems to be enough to prevent accurate and reliable manual focusing.

I tried using a focus chip on the Canon 50D but it worked sporadically and was not accurate. Maybe I should try it with the OM-D ? I also tried Focus Peaking but it is poorly implemented on the OM-D and the results were so-so.

Writing this makes me realize that maybe I should calibrate the viewfinder more often - before each birding session and when the light changes. Quite a hassle...

As you can see, you are not the only ones...

Please contribute with comments and suggestions. Add your experience if you also have eyesight problems. That way we can help each other and maybe find solutions.

 

[DanC.Licks]

Here is how I "solved" the problem for me. That is to say, how I got around the camera not having enough adjustment in the ocular of the VF. I just ground down a lens (plastic) from a cheep old pair of ready-made +1.5 reading glasses (frames were shot anyway) and fit it into the VF. It is held in place by a somewhat butchered Seagull eye-cup. It works very well and puts the focus of the VF back into the middle of the range. I still have to "drop" my glasses for shooting, but I find it impossible to focus with glasses on.






I have a nice coated glass lens of about the same magnification that came out of my butchered Canon 100-200mm zoom (TN donor) that I am saving up for the E-somethingorother. Much harder to work, but the quality is for sure much better. About the size of a 1€ coin, (US quarter), so there isn't that much to grind away.

 

[Mark9473]

I think reducing the glare on the LCD screen is the best option. Some tips:
http://www.wikihow.com/Reduce-Glare-on-a-Digital-Camera-Screen
You could even fully shield the LCD and just leave an opening for your eye.

 

[DanC.Licks]

I don't find using the LCD at all practical for shooting anything other than stationary subjects. It would also mean constantly switching between two pair of glasses. No, for me a VF, whether EVF or OVF is the best way to go.
Maybe a box with a magnifier over the LCD would work, but then only on mirrorless cameras. Live view is too impractical for shooting birds etc. with a "standard" DSLR.

 

[JGobeil]

Here is how I "solved" the problem for me. That is to say, how I got around the camera not having enough adjustment in the ocular of the VF. I just ground down a lens (plastic) from a cheep old pair of ready-made +1.5 reading glasses (frames were shot anyway) and fit it into the VF. It is held in place by a somewhat butchered Seagull eye-cup. It works very well and puts the focus of the VF back into the middle of the range. I still have to "drop" my glasses for shooting, but I find it impossible to focus with glasses on...

Nice work Dan ! You're quite a handyman. However, the diopter adjustment on the OM-D seems to be enough correction for me - it adjusts from -4 to +2.

Following your idea, I searched for alternate eyepieces that would improve eye contact with my OM-D and there is the EP-11. For those that have a OM-D, please note that the photo shown everywhere doesn't describe it well. The eyecup is much deeper than it looks. See the photo below that shows it at an angle.

I'm like you and I much prefer using the VF instead of the LCD except for casual shooting in family events where Touch Focusing on the LCD is quite nice indeed.

I think reducing the glare on the LCD screen is the best option. Some tips:
http://www.wikihow.com/Reduce-Glare-on-a-Digital-Camera-Screen
You could even fully shield the LCD and just leave an opening for your eye.

Mark, I have tried all sorts of shades for the LCD on other cameras and they don't seem to help much for my situation. In order to provide adequate protection from the sun, my eyes must be quite close to the camera and, if my eyes are too close, I adjust for a slight out-of-focus with my progressive glasses. In order to effectively focus using the LCD, the camera must be at least 50-60 cm away from my eyes; at that distance, the shade is not very effective unfortunately.

Also, the shade is quite an annoyance if you want to also use BOTH the viewfinder and the LCD. Not very practical. These shades are designed for cameras that only have a LCD.

Using a blanket over the head and camera works quite well but it is not very pleasant and it is VERY hot on a warm day.

 

[Tord]

I don't find using the LCD at all practical for shooting anything other than stationary subjects. It would also mean constantly switching between two pair of glasses. No, for me a VF, whether EVF or OVF is the best way to go.
Maybe a box with a magnifier over the LCD would work, but then only on mirrorless cameras. Live view is too impractical for shooting birds etc. with a "standard" DSLR.

I totally agree. The LCD is useful for static subjects only. It can be used for cooperative perched birds and in rare occasions for birds on water considering. I will start using the viewfinder first to secure at least one semi-sharp shot and, conditions permitting, will take a sharper shot using the LCD. But it takes precious time: putting glasses on, turning liveview on, engaging the liveview magnification, fine tuning the focus while waiting for vibrations to attenuate, taking the picture.

 

[Tord]

Dan, I am impressed by your skills. I'd like to reuse your design but I would have to sacrifice a pair of glasses to correct astigmatism and I guess I would need special tools to fabricate the lens from optical glass...

 

[DanC.Licks]

Yes, glass is much harder to work than plastic, no question. I used a small sanding wheel on my mini-lathe, but a grinding wheel will also do. Important is to keep the glass cool by dipping it in water.
I think it could be done. You would have to mark the center of the lens, where it is thickest, and the vertical axis, with a fine waterproof felt tip pen. An old pair of glasses would work, but why not (sweet)talk to your optometrist. Tell him what you have in mind and maybe he could provide you with some old (plastic!) lens that is close enough. You still will have adjustment for the diopter, so it would only have to have roughly the same off axis correction. Even if the angle is wrong it wouldn't mater. you would just have to look through and turn it till it is sharpest, and mark the vertical axis. Doesn't have to be perfect. Your eye will adjust somewhat. But it would naturally be nice to get it as close as possible. I also have a little astigmatism, but it is not enough to worry about for shooting. Just have to be able to see the markings on the focusing screen clearly. If they are clear, you are good to go.

As far as focusing is concerned, if I am at all in doubt I will shoot off a quick bunch and tweak the focus with the fine adjust. Might be hard to do if you are hand holding though.
P.S.
Love my LensMaster.....now!

 

[jovica horvat hori]

Magnifier

This is my solution for manual focusing.Using Live mode and 5x zoom when focusing, back to normal mode ,take a picture with remote switch.
Lens is 4 cm diameter , focus distance 10cm.Aluminium 0.5mm box flocked
inside with black textile.