Reveni labs collimator thoughts?

[Kcirtap]

Really interested if anyone has tried the device!

 

[MMfoto]

I'd like to have one. You can buy old ones for less, but they are usually very old. I wonder about the light sources and power supplies of 30-60 year old electrical devices. The Reveni is a fraction of the price of other new collimators.

 

[koraks]

For those interested in the background to this project, here's a thread that @Reveni-matt started when he was in the early phases of exploring the concept: https://www.photrio.com/forum/threa...dable-production-ready-autocollimator.210217/

Welcome to Photrio @Kcirtap !

 

[Dan Daniel]

Mine will be here later this week. Once I figure it out and get a chance to play, I'll do a post here. Maybe there are pre-production samples out there for testing and such. But basically he has just finished assembly and they are starting to ship.

Do you have any specific questions?

 

[Dan Daniel]

So the collimator showed up. The overall build is very nice. Nice materials, etc. Seems very sturdy and secure for alignment, etc. Optics all look clean.

The eyepiece cup isn't perfect, but works fine (a little prone to lose position).

The Siemen star is crisp. Very sharp. I'm seeing super fine resolution in the center. So the target is high quality. And very clean.

Testing a few cameras, things are looking good. So I am excited to have it and to be using it.

One problem is that the threads on the eyepiece for focusing are far too tight, at least on my sample. To turn the tube for getting precise focus means using two hands, torquing the whole assembly out of focus, and having to break loose the threads at a larger scale then needed for fine adjustment. I spent a few rounds of filing the threads (one part looks to be 3-d printed nylon or such) and overall diameter down to get a secure but functional focus action.

I wrote to Matt at Reveni about this and he said it is supposed to be this way (super super tight). So either my sample is off, he didn't understand the condition I described, or his idea of achieving fine focus and mine are radically different. Considering that there is a setscrew for the focus setting, I don't see the need for tightness that destroys alignment and isn't functional. Oh well. a little work and all is fine.

 

[OAPOli]

@Dan Daniel is there a reticle on the eyepiece? Generally the eyepiece focus is adjusted to the reticle and fixed there. And usually the collimator lens is left at infinity and you rack the focus on the test lens to see when it reaches infinity. If you need to do fine focusing it would be done on collimator lens when you're not 100% sure you have reached infinity on the test lens at its stop.

 

[Dan Daniel]

Not sure of the terminology and your use of reticle. But yes, the eyepeice is focused to the star when the objective lens is set at infinity. And then it stays there. Hence the set screw. I get snug threads, but there were, as I said, so tight that you need to stress and torque the mounting and have the eyepeice focus jump as the threads 'broke free' and snagged again. No way to do small subtle fine tuning adjustment. Anyway, I got the threads working for me and have the eyepiece focused and locked down.

 

[OAPOli]

I misunderstood; sorry.

Instead of reticle I should have used graticule. It's helpful for your eye in order to keep focus on the proper plane though the eyepiece.

 

[RalphLambrecht]

Mine will be here later this week. Once I figure it out and get a chance to play, I'll do a post here. Maybe there are pre-production samples out there for testing and such. But basically he has just finished assembly and they are starting to ship.

Do you have any specific questions?

what wold an amateur photographer use it for?

 

[Dan Daniel]

what wold an amateur photographer use it for?

I guess what anyone else would use it for? Checking infinity on a lens. It can also give a view of overall lens quality and point to possible assembly issues like spacing problems or alignment problems. More common to be owned by repair techs but if you have a few hundred bucks doing nothing and want a specialized toy to play with every now and then, go for it.

 

[MattKing]

Some amateur photographers here do seem to buy (and sometimes sell) quite a few lenses .......

 

[4season]

So far, I'm impressed with mine, as it makes even slight maladjustment easy to detect, and can be easily stowed away when not needed.

I initially had problems with the USB dimmer's female connector not making good contact. This was due to excess molten plastic having oozed where it didn't belong during manufacture. I cleaned this up with a hobby knife.

 

[OAPOli]

what wold an amateur photographer use it for?

You can use it as a telescope to check the moon.

 

[4season]

Eyepiece fell to the floor this evening, but appeared undamaged. Had only lightly torqued the single, small setscrew which holds it in place, and this had come loose. Decided instead to stick a small piece of polyimide tape to the eyepiece barrel and rely on friction to keep it in place.

 

[RalphLambrecht]

You can use it as a telescope to check the moon.

The mom needs checking. The last time I checked it, it was OK.

 

[Reveni-matt]

So the collimator showed up. The overall build is very nice. Nice materials, etc. Seems very sturdy and secure for alignment, etc. Optics all look clean.

The eyepiece cup isn't perfect, but works fine (a little prone to lose position).

The Siemen star is crisp. Very sharp. I'm seeing super fine resolution in the center. So the target is high quality. And very clean.

Testing a few cameras, things are looking good. So I am excited to have it and to be using it.

One problem is that the threads on the eyepiece for focusing are far too tight, at least on my sample. To turn the tube for getting precise focus means using two hands, torquing the whole assembly out of focus, and having to break loose the threads at a larger scale then needed for fine adjustment. I spent a few rounds of filing the threads (one part looks to be 3-d printed nylon or such) and overall diameter down to get a secure but functional focus action.

I wrote to Matt at Reveni about this and he said it is supposed to be this way (super super tight). So either my sample is off, he didn't understand the condition I described, or his idea of achieving fine focus and mine are radically different. Considering that there is a setscrew for the focus setting, I don't see the need for tightness that destroys alignment and isn't functional. Oh well. a little work and all is fine.

Hi Dan, I didn't hear back from you after my email reply. I assumed all was well.

The movement of the eyepiece has a small impact on the focus of the target on the mirror. I set each one to an approximate focus (good to my eye) and the fit is intended to be tight, as mentioned. Gripping the Autocollimator body is required to adjust it and if it is bumped out of alignment, finding the reflection in the eyepiece again is usually a quick job, but this would depend on how fiddly your mounting setup is and how many joints and axes you could knock loose.

The eyepiece focusing doesn't need to be done often, possibly only once. Hence the set screws and tight fit are a benefit, in my opinion. I also didn't want it to wear in and loosen too much over time if someone was doing a lot of refocusing, like if they were sharing the unit with someone else and the two of them found the eyepiece needed a lot of adjustment between the two of them.

I will tell you a trick I found when doing it, I would have the eyepiece loose and would push and pull it within it's tube to find the focus, then observe how much of a gap there was between the ridge stop on eyepiece and the tube end, and since I know the thread is 2mm per turn, would estimate how much of a turn was needed to approach the correct position. Doing this meant I could dial it in with only two or three adjustments of the screw. I was dialing these eyepieces into place in under 15 seconds with the Autocollimators mounted on a tripod.

Hope that helps.

 

[Reveni-matt]

I misunderstood; sorry.

Instead of reticle I should have used graticule. It's helpful for your eye in order to keep focus on the proper plane though the eyepiece.

There is not a graticule, but one can be installed in the eyepiece if you wish. It is not an adjustable eyepiece, so focus on a graticule cannot be adjusted. If you find it would help your eye in some way, you can install one easily.

Adjustable eyepieces can be used and must have a graticule installed to ensure the eyepiece is kept in good focus with respect to the reference mirror, or it will skew the results when testing a lens.