DIY anamorphic lens - Page 73

andy238 · 15th September 2006, 01:11 PM

Nice job, Steve! Looks like you've got a great setup. I'm following your progress closely

I just ordered my prisms a couple days ago. Anxiously waiting their arrival!

Andy

Mark Techer · 15th September 2006, 03:22 PM

Quote:

Mark, did you wind up ordering any of the US wedges? Just wondering if anyone is going to do a first hand comparison of the Aussie trophy optics to the US trophy optics.

No, I got mine is Australia. The have a steeper angle and are thicker at the base, but I would say thay are made of the same stuff, so should perform the same.

The interesting points I raised previously seem to have proven correct.

1. A prism (any two non parallel surfaces regardless of the angle) will work to bend light. Steve's prisms are just 5 degrees, where mine are closer to 15degrees.

2. It is the angles of the front and rear faces that affect the amount of stretch. The results are the same for both mine and Steve's lens, and looking at the photo he posted, the angles of both the front and rear prisms faces are the same...

Mark

Steve Scherrer · 15th September 2006, 03:37 PM

Just looking at the pictures I posted again, and they seem a bit hazy--this is not what I saw at all, and is an artifact from the camera I am using. I have the camera set up on a tripod. Does anyone have a good camera setting to take good screen shots?

Also, some other observations. Last night, any distortions were pretty much confined to the right side of my screen, including pincushioning issues and CA. In fact, you can see some CA on the pictures I just posted running down the right side of the screen. I am absolutely convinced that playing with the angles of the prj, the housing and the prisms will get rid of these annoyances (and as you can see, I pretty much eliminated the geometry distortions).

I noticed that when I was adjusting the footings of the pj with the housing in front of the pj, the image, when moving up and down, was "wavy" as it passed through different parts of the lenses. This is an indication that the prisms are not absolutely clear and free of internal striations. But once the pj is settled and the image remains in once place relative to the prisms, there is absolutely no noticeable distortion due to this. It's just a product of slight imperfections in the crystal, and I think you would be hard pressed to get better than this. I would be interested in playing with the solid Pr*sonic wedges to see if these do the same thing--I would imagine they do.

Since I am pretty resigned to the fact that achieving true 21:9 form a 4:3 pj is probably not going to work, my job gets much easier, in that I only have to have two settings on each prism to dial into--passthrough and stretch, like the Pr*sonic. Whether it is in front of a 4:3 or a 16:9 projector, it should work the same, and the settings should stay the same to achieve ~33% stretch.

mfeidler · 15th September 2006, 04:12 PM

I looked at the 5" x 7" prisms locally available from a trophie shop and they looked awesome. They just wanted more for them ($59)plus tax too.

I called Massilon Plaque this morning and ordered two of the J24, 4" x 6" Prisms for $29.00 ea. I spoke to Suzan. She said to tell everyone to call her and order them. The price was better than the internet price.

800-854-8404 ext. 226

Now I just have to wait!

I guess I will start shopping for my screen. I decided the other night that 130" wide 16:9 was just a tad too big for my seating distance. (Too much eye movement for a 2 Hr. Movie) I still want to see if I would like 130" wide for a 2.35:1 aspect. If not I may go to a 116" wide screen.

Mike

roar · 15th September 2006, 04:58 PM

Thanks for the updates Steve, pictures look great. I'm hoping to check Buds work out when he is ready too! He has the exact projector I want to buy so it will be a great demo for me...

Bud has invested in 4 lenses... any thoughts on expectation of picture quality with the 2 vs the 4? Mark, I believe you had said you ordered 2 more to test that very thing, any luck?

Mark Techer · 16th September 2006, 01:33 AM

Steve,

The last set of photos I took, I just used "natural".

mfeidler,

If your going to have a 16:9 screen then times the height by 3.68 to get your seating distance. If you go a scope 235 screen than you can times the width by 1.54.

roar,

I am in the process of making a 4 prism lens, but have not ordered the second set yet. It is said that there is a 70% improvment over a 2 prism lens...

Mark

Steve Scherrer · 16th September 2006, 03:17 AM

Quote:

Originally posted by Mark Techer

roar,

I am in the process of making a 4 prism lens, but have not ordered the second set yet. It is said that there is a 70% improvment over a 2 prism lens...

Mark

70% seems like a lot. But 70% of what? Not sure what this means...

Mark Techer · 16th September 2006, 05:25 AM

70% improvement includes way less CA, barrel/pincushion etc...

That is why I am looking forward to getting another set of prisms soon...

Mark

roar · 16th September 2006, 07:38 AM

Quote:

Originally posted by Mark Techer
Steve,

The last set of photos I took, I just used "natural".

mfeidler,

If your going to have a 16:9 screen then times the height by 3.68 to get your seating distance. If you go a scope 235 screen than you can times the width by 1.54.

roar,

I am in the process of making a 4 prism lens, but have not ordered the second set yet. It is said that there is a 70% improvment over a 2 prism lens...

Mark

70%? You ever watch The Mask when JimCarey's character see's Cameron Diaz's character for the first time and his jaw hits the floor? That's what mine just did

Impossible I say! Prove it

(Just kidding of course, hopefully I'll be able to see it action personally!)

Mark Techer · 16th September 2006, 09:26 AM

Quote:

Originally posted by roar

70%? You ever watch The Mask when JimCarey's character see's Cameron Diaz's character for the first time and his jaw hits the floor? That's what mine just did Impossible I say! Prove it

(Just kidding of course, hopefully I'll be able to see it action personally!)

I did build a 4 prism (water prisms) lens a while ago and worked really well, until I got inventive, hinged the main prism bodies and could not get proper stretch anymore. This is why I went back to a 2 prism lens.

The 70% quote actually comes from Prismasonic who claim that they have tests to confirm the improvment. I must say that I did see a huge improvment with my 4 prism lens when it was up and running. If you go back (many pages now), you can see some images I posted from it including that Jango Fett shot...

Lately my focus has been simply on getting a lens with solid clear prims - and we have done that - so now comes time for tweaking

Mark

16th September 2006, 01:33 AM	#726
Mark Techer diyAudio Member Join Date: Aug 2005	Steve, The last set of photos I took, I just used "natural". mfeidler, If your going to have a 16:9 screen then times the height by 3.68 to get your seating distance. If you go a scope 235 screen than you can times the width by 1.54. roar, I am in the process of making a 4 prism lens, but have not ordered the second set yet. It is said that there is a 70% improvment over a 2 prism lens... Mark __________________ CIH Explained

16th September 2006, 05:25 AM	#728
Mark Techer diyAudio Member Join Date: Aug 2005	70% improvement includes way less CA, barrel/pincushion etc... That is why I am looking forward to getting another set of prisms soon... Mark __________________ CIH Explained

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15th September 2006, 01:11 PM	#721
andy238 diyAudio Member Join Date: Jul 2006	Nice job, Steve! Looks like you've got a great setup. I'm following your progress closely I just ordered my prisms a couple days ago. Anxiously waiting their arrival! Andy

15th September 2006, 03:37 PM	#723
Steve Scherrer diyAudio Member Join Date: May 2006	Just looking at the pictures I posted again, and they seem a bit hazy--this is not what I saw at all, and is an artifact from the camera I am using. I have the camera set up on a tripod. Does anyone have a good camera setting to take good screen shots? Also, some other observations. Last night, any distortions were pretty much confined to the right side of my screen, including pincushioning issues and CA. In fact, you can see some CA on the pictures I just posted running down the right side of the screen. I am absolutely convinced that playing with the angles of the prj, the housing and the prisms will get rid of these annoyances (and as you can see, I pretty much eliminated the geometry distortions). I noticed that when I was adjusting the footings of the pj with the housing in front of the pj, the image, when moving up and down, was "wavy" as it passed through different parts of the lenses. This is an indication that the prisms are not absolutely clear and free of internal striations. But once the pj is settled and the image remains in once place relative to the prisms, there is absolutely no noticeable distortion due to this. It's just a product of slight imperfections in the crystal, and I think you would be hard pressed to get better than this. I would be interested in playing with the solid Prsonic wedges to see if these do the same thing--I would imagine they do. Since I am pretty resigned to the fact that achieving true 21:9 form a 4:3 pj is probably not going to work, my job gets much easier, in that I only have to have two settings on each prism to dial into--passthrough and stretch, like the Prsonic. Whether it is in front of a 4:3 or a 16:9 projector, it should work the same, and the settings should stay the same to achieve ~33% stretch.

15th September 2006, 04:12 PM	#724
mfeidler diyAudio Member Join Date: Sep 2006	I looked at the 5" x 7" prisms locally available from a trophie shop and they looked awesome. They just wanted more for them ($59)plus tax too. I called Massilon Plaque this morning and ordered two of the J24, 4" x 6" Prisms for $29.00 ea. I spoke to Suzan. She said to tell everyone to call her and order them. The price was better than the internet price. 800-854-8404 ext. 226 Now I just have to wait! I guess I will start shopping for my screen. I decided the other night that 130" wide 16:9 was just a tad too big for my seating distance. (Too much eye movement for a 2 Hr. Movie) I still want to see if I would like 130" wide for a 2.35:1 aspect. If not I may go to a 116" wide screen. Mike

15th September 2006, 04:58 PM	#725
roar diyAudio Member Join Date: Jul 2006	Thanks for the updates Steve, pictures look great. I'm hoping to check Buds work out when he is ready too! He has the exact projector I want to buy so it will be a great demo for me... Bud has invested in 4 lenses... any thoughts on expectation of picture quality with the 2 vs the 4? Mark, I believe you had said you ordered 2 more to test that very thing, any luck?

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