A Note About The Redrock M2

Adam_Levins

Adam_Levins

Active member
Some of you may have noted the problems I have had with the redrock in earlier posts.

I did all the stuff described on this forum and redrocks forum but it was frustrating and nothing seemed to work.

I kind of gave up on the unit and my HVX and have gone back to shooting on super16.

I decided to rent the unit out and this week it has been on a shoot in Malaga in Spain.

They had another redrock unit on this job and when they set mine up to match the other unit they noticed the softness at the edges that I have been complaining about. After much trial and error they found the problem.

THE LENS IN THE ACROMAT HAD BEEN MOUNTED THE WRONG WAY AROUND AT THE REDROCK FACTORY.

This was not something I had even considered but since they had two units they could compare the two and find the problem.

Both sides are convex but one slightly more so than the other.


It is all working well now but I had to learn this lesson the hard way (shot a project on it the wrong way around) and I just wanted to let you all know that this might be a issue with other units.

Have others noticed this same issue?

All the best,

Adam
 
I have had this same problem with my M2 and after following all the tutorials and suggestions on the Redrock Forums I've just about given up.

So yes is there a way to remount the lens without damaging it? Or should I judt contact redrock and have them remount it or send me a replacement?

Thanks,

Juan
 
That's very disappointing. Don't they have some basic QA processes in place to make sure the gear that leaves the factory meets their specifications?
 
Its a slip up i guess, not a big deal if you test equipment before a shoot and have a good planning for a shoot in place before you shoot. If you are un organized and in a rush, then well, idunno. If you never expect a problem with anything, thats not a good way to think
 
Cynic, I think you misunderstood. The achromat was assembled incorrectly, and that should have been caught at the factory during the QA process. In fact, a skilled worker should never have assembled them incorrectly in the first place.

There is no way that someone shooting with the gear would be able to pinpoint the cause of the poor results without having a second set of gear to compare to, and even then there may not be any discernible physical differences.
 
Good info. Sux it screwed the pooch on your gig. It took me a few days of shooting to trouble shoot the problems when i used the M2.
 
Hi Adam,

That's interesting to say the least. I have a Red Rock that I have done focus chart after chart with and have never been satisfied with sharpness. I had come to the conclusion that it must be me, since everyone else has been raving about the M2.

I will call them, and reference your issue. When did you receive yours

Thanks,

Rob
 
Last week, Brian at Redrock helped me set up my M2. I was having a couple of issues, both of which have been resolved.

One issue was mechanical (this may not be applicable to your focusing problems, but I thought I should mention it). We 'lowered the motor' inside the M2 so I no longer need to be at Z99 (!) to get a clean fullframe image. Sounds complicated, but it was really just a matter of opening the M2, loosening a couple of screws, lowering the part, and refastenig the screws. I believe this procedure has been discussed on the Redrock boards.

With regard to setting your backfocus, make certain your 35mm lens is set to f16, while your camera iris is wide-open. This will allow you to see the most grain for backfocusing purposes.

I will say that before conversing with Brian, I was about ready to give up on the M2. But Brian was incredibly helpful, and now I feel much more confident in using it. After properly configuring it, we did a focus chart and it looked great. (BTW, I'm using a DVX.)
 
Cynic821 said:
Its a slip up i guess, not a big deal if you test equipment before a shoot and have a good planning for a shoot in place before you shoot. If you are un organized and in a rush, then well, idunno. If you never expect a problem with anything, thats not a good way to think
Click to expand...

I'm going to do more testing before I contact Redrock. I agree that you shouldn't go out on a shoot before properly testing and becoming familiar with new gear, but I've been testing and tweaking this sucker for over a month now and I still can't get edge to edge sharpness. I've followed all the online tutorials, read all the posts on RedRock's forum, and read the printed manual. Frankly I'm getting tired of testing rather than shooting. I've had several projects happen in that time and I've put off using the M2 until I know I can get an acceptable image. I'm really happy with the cinematic quality of the images rendered by using the adapter, but I don't want to use it on a project while I'm getting that fuzzy, defocused band on the right side of the frame.

Since I don't have access to another Redrock achromat, I've just assumed that there's still something I'm doing wrong with the setup. The only clue I've had that it wasn't me is when I shot some test charts with just the achromat (no M2) at close range. I noticed how inconsistent the focus was on the image so I don't think it's an issue with the placement or alignment of the cinescreen.

This is a very interesting thread because tomorrow I'll try replicating my tests with the achromat on backwards. To bad it's not threaded on both sides. Hooray for gaffer's tape!

Anyway, I'll let you know if this solve's my problem. If it does then I'll contact Redrock about replacing or fixing my achromat. I'll post again, once I've done further testing.

Juan
 
I guess the main problem it that you just wouldn't think of this when trying to resolve issues. They had two units on the shoot so spotted the problem on closer inspection.

It's quite easy to flip the glass inside the acromat on the side that mounts on the camera there is a threaded plate on the inside. This comes off and the glass can be removed and flipped.

The problem is in knowing which way is right. As I mentioned they are both convex but one side more so than the other.

I did prep the camera package at Panavision in the UK before my shot and we just thought in the end (after about 3 hours of messing about with the unit and a spectrometer) that that was the way it was supposed to look.

Thanks Sean for the info, this is all stuff I had done (and more) but if the glass in the acromat is the wrong way around, you aren’t going to get a good image so this is a totally separate issue to the fine-tuning stuff you mention.

DVinsight, I have had my redrock for about 8 weeks, hope you reslove you issue.

All the best,

Adam
 
Hey Adam,

as i understand, you changed the glass now, to be on the right side?
How is it working now?

All right with it, can you go and shot with it?
After seeing some footage, i become more andmore convincedthat this could be a nice tool for my future...but not sure yet...!
 
The unit was on rental in spain this week. they found the problem and have reported all to be working well now. I will have a look at it when I can but I am off from tomorrow boating from Denmark to Paris and will be away for three weeks.

I shot an entire project with the thing the wrong way around and just put vinyet around the frame to hide the softness. you cane see the results here:

http://www.dvxuser.com/V6/showthread.php?t=67134

I too have seen some very nice footage with the unit and am keeen to work kwith it as well but the band I am doing my next video for "Second Person" saw the last video that I did with the unit and want me to shoot on super16 for there project and I can understand that.
 
So have a good trip Adam,

if the band can pay super16, no problem, do it like this for the gig and check that everything worksright now with the m2 and enkoy..curious to see more footage!
 
Hi All,

Thanks for bringing this to our attention. This is the first we've heard of this kind of issue, but if you think you have a 'backwards' achromat, just drop us a line at support@redrockmicro.com and we'll get you the help you need. Also, for those of you who feel like you need some additional help with setup you can drop me a line directly at bvalente@redrockmicro.com or if you are in the LA area we can support you directly.


Thanks

Brian
 
Thanks for doing all you can ensure your customer's satisfaction. I had loud motor problem, Brian sat down for at least an hour and described, in great detail, how to go about fixing the problem. Now iam on my 3rd commercial and 4th music video, and every client of mine LOVES the look of the redrock. Thanks again for a wonderful product.
 
How are we to know whether our achromat is correct or not?

I am quite frustrated about the vagueness about set-up with these units and how hard it is to get clear information despite posts on their website.

Just how sharp should i expect corner to corner sharpness get?

I can get all the corners and the center to focus at the same time, but the corners are definately softer than the center.

Is this as good as it gets or is my achromat mis-assembled?
 
I noticed that the achromat has "Redrock" printed on the side, correct? To make sure my achromat is on correctly, (which I am %99.9 that it is considering the awesome clarity of my image), should the words be rightside up when viewing from behind the camera body, or should they be rightside up when viewing from in front of the lens?
 
Adam_Levins said:
It's quite easy to flip the glass inside the acromat on the side that mounts on the camera there is a threaded plate on the inside. This comes off and the glass can be removed and flipped.
Click to expand...

Thanks Adam. I did some followup tests and it does seem like my achromat is mounted on backwards. I shot some charts with just the achromat, holding it in front of the HVX lens backwards, and the difference is night and day.

So I'm trying to remount the glass but I'm having a hard time removing the ring that holds the lens in place. Did you have a hard time doing this? I'm using the two notches on the ring to try to get it to turn, but it seems like it's on pretty tight. I'll keep trying but I'm afraid I'm going to accidentally scratch the lens.

Thanks,

Juan
 
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