Perhaps for rental?

Unsharp Mask applied in Corel PhotoPaint v5
 

Hey Dan,

is it just the lens,

or does the "Unsharp Mask applied in Corel PhotoPaint v5"
mean that a large part of the effect was in post??

<<<Perhaps for rental?>>>

to be honest Brett, when I will get one of those (for my soul) I will accompany it out each time (with insurance in place)
Let's get real here.. in the DV and lately HDV world, the production budgets are minuscule. Some camcorders sell for less than that lens alone... need I go on?...

<<<<<is it just the lens,?>>>>

....sadly ....yes....is just the lens.... sigh.......

These are just two samples of all the multitudes of writing I have seen about people saying they need a diopter/macro to be able to focus on the GG.

I disagree. What they mean to say is "I need a diopter/macro to be able to focus on the GG *if I put the GG close to my camera*"

I have been doing a lot of tests on my adapter and I've found that you can go one of two ways: You can use a diopter, or you can simply use a really long extension tube between your camcorder and your GG. The longer the tube, the more you can/must zoom in... and the more you zoom in, the smaller your camera's field of view, and therefore, less vignetting.

This second method seems to be what the Guerilla35 guys are doing too. Take a look at how long their adapter is. I ended up building basically the same thing by trial and error.

The biggest advantages to using more distance between camcorder and GG are 1) you don't need pay for diopters, and 2) you eliminate vignetting.

The biggest disadvantage to using more distance between camcorder and GG is that you have a really long adapter.

Thoughts, anyone?

I think that you are right on the money, but the obtrusiveness of a long tube is going to be problematic - but I am going to try it anyway. If I can save $200 by including a long tube, I am going for it and seeing what happens. I will post results tomorrow.

Also, I checked out the Guerilla35.com guys and they have no pictures of the unit, how did you know they did the tube thing?

second that!

Using one mirror will also increase the distance and put your camera in an angle which is less clumsy to shoot with.
The mirror could even be placed after the GG, like a still camera.
I wrote this somewhere else too:
If you have a LCD screen that can be flipped and closed to the camera, you can look it when the camera is at 90 deg. I'm not sure, but maybe the image will be correct (in stead of mirrored.)

I made a drawing:
http://s01.picshome.com/c7e/setup.jpg

I think if the mirror is put after the GG (unlike the drawing) the distance to the camera will be increased, but dust on the mirror will be a bigger problem.

There are pictures of the Guerilla35 device, but you have to go into their forum to see them. Here are the shortcuts:

http://www.guerilla35.com/talk/viewtopic.php?t=8

http://www.guerilla35.com/talk/viewtopic.php?t=9

It looks to be a 52mm tube, with an SLR-format GG at the end. Looks like no condenser, either! Which if true, further backs up the notion that zooming in will get rid of vignetting.

I find my long tube a bit funny looking, sure, but if you are filming a movie, that doesn't matter at all. A steadicam-style body-mounted stabilizer is pretty darn ridiculous looking, and so it's not like a prosumer camera is small in the first place, especially when it's equipped with a huge lens hood or matte box, a big mic, an eyepiece extender, follow focus, rails, etc!

For documentary or interview work, some might think the long tube is obtrusive, but in reality, your subjects are going to react more to the fact that you have a giant camera pointed at them. The extra 2" of tube are the least of their concerns!

Thanks for the input, Dan. I'm always interested to see what you've built next.

funny, but... you asked for it:
yesterday I had to build a replica to this:

http://www.knightsedge.com/medieval-...apult-4804.jpg

(my younger son's school project) It does not look like much, (even now when I look at it) and it seems like one hour project but keeped us busy for 8 hours.... we are one "knight sword" away from completion.... (to everyone's luck, we are roughly 500 years away from mass distruction weapons..lol) I will keep you updated with the progress if you wish...

Well, using my camera, to get in focus, zoom in as far as I can go - the object needs to be...wait for it...30+ inches away ( that's right, about 2.5 feet). Much too far indeed. I can't work with the tube. Oh well, had to test to be sure.

It's also interesting that I don't see the artifacts from a static GG in the Guerilla35 footage. I wonder how they accomplished that?

Mandy, most demo footage is compressed with a low bit rate to make file sizes small. ( and to hide grain !!!! ) It so happens that the first thing the compression 'throws away' is the grain. Stills are obviously useless in evaluating these adapters because you can't see fixed pattern grain in a still image.

When I post my demos I use 8 or 9 megabit data rate in Media9 to avoid this 'feature' .

Ok, that sounds reasonable, but from reading the forum some other people have seen the footage first hand and they say it looks great. I guess it will be wait and see.
I wonder how they are dealing with interchangeable lenses - the focal length will have to be changed each time - unless it only works with one lens type only.

back focus vs/ focal length
 

i dont think they are the same.... unless i am missing something...

Mandy,

I do not mean to zoom in as far as you can go. No way! I am talking about using SOME zoom.

For example, I put mine just at 3X zoom, then bottom out the focus and go up 15 clicks from there. That is perfect for a tube which is about 1.25" long as I recall (it's not in front of me to measure, and I have built several versions).

There is no reason to zoom in as far as you can go.

Sarena, you are right. Back focus is totally separate from focal length. And to answer your question, Mandy, the G35 pics show examples of three different mounts. I assume these are Nikon, Pentax, and Canon. I believe they said you can buy the mount separately and use your same tube.

These are all answered on the G35 forum.

I am not buying a G35 since my adapter works great, so I'm not shilling their product here, but I think it's funny that a lot of people have this cynical prejudice that the G35 guys are sitting there trying to hide grain, hoping to trick a bunch of people when the device first is available. I don't get that impression at all from watching those guys And that would be a pretty silly idea to attach one's name to or try to build a business around.

The real issue is whether the G35 guys' *opinion* of how much grain exists or is tolerable, compares favorably to other people's opinions.



Nice catapult, Dan! :) Anyone who has built anything complicated knows it takes many times longer than you think it will take, so 8 hours is very good!

I've just gone roughly through this thread, so maybe this is asked before, but how does the catapult make a circular uniform motion? And do you think it is usable for MF lenses too?

Oscar,
the catapult don't have nothn' to do with GG (yet, lol)
(It may come handy for the whole converter though...... rotf)
It was just what I had to built lately (son's school project) and Bill said:
"I'm always interested to see what you've built next." Zeat's all. (still rolln'...)
But I agree we should stick to the thread (although is sooo fun to slide at times...)

Still a bit puzzled, are you going to fight a guerilla35 war with your sons catapult?
Stick to the thread...is the catapult finished? If he's really your son, why did he need your help?

Heres some more facts:

1)Every model video camera (and thus its built in lens) has a different minimum focus distance it can achieve for a given field of view. Basically this means if your not using a diopter then your particular camera may or may not need a extension tube. And if you do need a extension tube it may only need to be short or you may need to make it very long. EACH CAMERA IS DIFFERENT - test your own to find out the facts.

2)Generally speaking if your not using some form of a condenser lens then the longer the extension tube the less you will notice light fall off in the edges of the frame (ie. hot spot). This happens because the scattered light from the GG doesnt have to bend as such a tight angle if your looking at the GG from a distance (ie extension tube). Just hold up your adapter close or far from one eye and see for yourself.

3)MF focusing screens are designed to fix both of these problems and thus your adapter will not need a long extension tube or a diopter anyways.

4)You also dont want to put the GG extremely close to the video camera either because you will get a distorted view of the GG AND your video camera will not be able to keep the entire GG in focus at one time.

5)Learning the basic in optics will reveal what is happening to light with different lenses and GG and you will not need to do nearly as much trial and error. Google the optical components that go into these adapters and make your adapter work like you want it to work.

Speaking of getting off topic, by coincidence I got the chance to view the raw footage from the latest G35 demo. There really is no grain at all.

To answer Mandy's comment, "I wonder how they accomplished that," it was not done by compression as others have postulated. It was done by an expensive, labor-intensive screen made for them, and a lot of homework. They didn't just start a few months ago. I got the chance to talk to Jonathan of Guerilla35 and was surprised to learn how much thought and work was put into their deal.

The product is also not what I thought it was (I thought it was simple a GG and condenser on a long tube).

I spent $150-200 on my first tube and have revised it multiple times. I've probably spent another $50-100 on bits and pieces. I have some condensers for my GG on the way, and a Beattie as well, so that's another chunk. I derived a lot of enjoyment doing it but in retrospect I wish the G35 were available because $300-400 for an adapter with grain is not that far from $800-900 (i think) for an adapter with no grain whatsoever. Gotta save them pennies!

Yeah Brett,

I am learning about the close to the GG thing. I am trying anytihng right now to get this thing working. I have put the GG and the camera very close, but I am still getting blurriness around the edges. Must be too close.

Also, how can one tell the strength of an achromat - for example, this one

http://www.surplusshed.com/pages/item/l1590.html

You can tell the power of an achromat paetly by its focal length. Genereally shorter the focal length the stronger the achromat. You want your achromat to have the proper focal length to send all light going thru it towards a common target at a specific distance (the CCD). Find the angle that the light must bend to hit that target and you have the means of finding the proper focal length for your achromat.

Or you could always just buy a Maxwell or Beattie screen.

All I can comment on the achromatic is this: for that price, go for it (but it all adds up!)
and if you can get away with it... let us know...
but then again: if those would be a suitable replacement, how come Century is still in business ? just wondering...

(I bought mine from Century,(btw) the screen from Beattie, and some other parts of the best I could find....including US $ 80 for the motor itself! all this having "oriental replicas" on the table @ $0.25 each!)

here is another link I just found:
http://www.angelfire.com/ca/erker/closeups.html
They might work with some camcorders (as long as the diagonal exceeds the diagonal of the format).

WEll, to do that, I would have to scrap all of my DOF machine plans at this point because I am using the spinning GG and going to a Maxwell or Beattie screen would cause me to go the oscillating machine route, which is a long long road. I still want to try this spinning GG until I can'ts tries no more! The achromat that I was looking at
http://www.surplusshed.com/pages/item/l2076.html

is starting to look good because the focal length is short 80mm FL ( I wonder the strength that would be) and it is clear coated - so this might be a winner for me. What do you think Brett?

Here is another link:
http://shop.mellesgriot.com/products...=1034&mscssid=
It looks like it comes from the same manufacturer. z'got to be something "just about" with the $9 ones.... but at this price, you can't go wrong.

Yep, I just found the exact same one at Melles Griot. There is something going on, definitely, probably a second, a scratch or some minor abberations or something. I want to spend the $9.00, but 31.5 mm is a small diameter for my camera - considering the thread is 43mm...hmmm...it makes me think. I wonder if it will matter?

If you check out
http://www.anchoroptics.com/catalog/...d=14&start=226
They also have the achromats, but they are graded as well - and more expensive, even for the Grade 3's.

I am still trying to find another source of lenses!

I wish I could help you further but as explained before each camera is unique. Not to mention how you build your adapter is unique as well. I'll I can do is recomend that you follow some of the things I have listed above. After that only person that can answer your questions will be you because each project is unique.

Of course I understand what you are saying Brett, that is why it makes creating a universal adapter sooo hard! I guess James Hurd has a way of making an achromatic lens, so it is possible, just how, I have no idea!
I think I am going to splurge and get the one at Surplusshed to see what it is like. After that, I am going to continue to test and see what the best distance for my camera is - and I am still unsure whether I need a condenser or not - there seems to be some question about if it is necessary or not.

Hello all,
I had planned on starting this thing already, but I've been tied up trying to close a deal on a house. Hopefully in the next week or so I can get started.

But anyways, here's a link that I was most likely going to buy from: http://www.edmundoptics.com/onlineca...?categoryid=10

They have some high quality lenses and a few lines that are cheaper priced.

Here's one for achromats specifically: http://www.edmundoptics.com/onlineca...=1749&search=1

These are 35% off: http://www.edmundoptics.com/onlineca...=2396&search=1

These links may provide some help in determining what lens you need/want: http://www.physics.uq.edu.au/people/...r/achromat.htm

http://www.usa.canon.com/html/eflens...y/index_a.html



Court

Thanks for the links and welcome aboard.
As near as I can figure... the prices are close for nearly the same quality...(no shortcuts there)

So,.... the latest stills from footage I posted on my site are showing some activity (counter wise) but no feedback. Still unacceptable? Not even Felix ?(the cat) Colors not OK? Vigneting? Soft focus? (hair on Felix)?
hmmm.....I wonder....
could it be that..."if one can't say something nice, should not say anything at all" ???
yeah.... that's what it is!... I have to check the pictures again and delete the offenders!
Oh well...... One can't please everyone at all times (I guess).....
Obin? Sarena? Frank? Where did everybody go? (me want nano35)

No one is posting? I think the whole "Work samples" folder is off topic, because I can't find any picture of a catapult.

Felix is some very sharp and absolutely perfect footage. Some guy here would say something like: YOU ARE THERE!!! BRAVO!!!

Album A CU is also very good.

No one is posting... everyone is quietly thinking, how damn he did it ;-)

Gents, thanks for your comments.
Now..I do not suppose anyone would give up the wonderfull "head-scratching-time" associated with groundbreaking teritiries?... hmmmm...theritorys? hmmm... lands! (yeah.. that's got to be it) and purchase the plans, would you? Derz a huge diff between my posts heer and my work.
Opposite spectrum. (if it wasn't for the results on the site and just by reading stuff on the net, I would have had a hard time believing that myself! lol) You must be registered on this forum to do zeat and must have contributed an answer or two on the subject. So..... hunting from the shadow does not work hear. As you can see, derz nothing to be sold anonimusly? ano... arghhh.... PRIVATE from my site and I do not plan to make a killing out of it. Is just help for those that need it and will have a very limited distribution. I am a real person with a real address, not a faceless POBOX (what I mean to say is that I am accountable for it) You must also sign a contract that the plans you will receive are for yourself and ONE UNIT ONLY will be built for your personal use. If you want to take it to the next level, we can make different arangements...
I need to see interest on the matter to move on. As a start, it will take 10 different comments (following this one) to post on line a short clip I have sent to P+S in Dec 2004 (now declassified) Is the movement I have made in the July-Aug last year. If you can make something out of it, good for you.
So.... der it is! does anyone wants any of it?

Best image I have seen yet on the LCD's of Z1/FX1:

http://dandiaconu.com/gallery/albums...0594.sized.jpg

http://dandiaconu.com/gallery/albums...0631.sized.jpg

Dan show me some footage shot with the sony hdv cam and your adaptor..I would LOVE to see some! also what is with your follow focus system? looks great..can I buy one for the micro35 I am building?

I have the tests on tape, I do not have the NLE and the Z1 now to import and so on.... and I am not sure about the whole process in Premiere Pro. I do not know anything else (Avid or FCP) What do you want me to do?
I can assure you of this: if it was not N E E D E D all I have done, I would look like an idiot to take the longest path ignoring the short cuts (or unable to spot them) FILM OUT is what I had in mind from the beginning and now, the image is as good as I have ever seen (and I have seen enough static and otherwise GG and Fresnel to tell the difference)

"the image is as good as I have ever seen "

Dan, is not that I don't belive you or something.... but I'm curious to see some images.
I've downloaded hundreds of megabytes of clips since FX1/Z1 arrived. Now I'd be happy to download some other hundreds of megabaytes of images with the deadly combination you're talking about! :)
Z1 with your adapter!

And then what? Are you ready to spend real dough on a real thing?.....
I have the footage. Nothing spectacular, just a test. It shows an image as good as the best hi rez pics on my site. (footage though). Something like this:
http://dandiaconu.com/gallery/ALL-CLIP-TESTS/IMGA0287
Every frame is just the same as those. Is just a matter of import/compress.... I would be interested in geting some low light images (whatever can not be captured by means of ordinay GG) but that means some set up...It will come anyway...but I have other priorities for now.