Letus back focus adjustment ring at DVinfo.net

Robert Bec · March 25th, 2009, 12:21 AM

I like to purchase a used letus extreme do i need the Letus back focus adjustment ring or can i do without for now

Rob

Bob Hart · March 25th, 2009, 12:47 AM

Robert.

You can do quite okay without the Elite backfocus.

As long as your used Letus Extreme has not been interfered with and damaged internally or has electrical issues, you should be fine. If infinity focus falls short with the wider lenses like 35mm, 28mm or the ultrawides like 20mm and 14mm, then it can be adjusted.

If you have the opportunity to try it on your camera before you buy, do so. Depending on how hard it may have been kicked and beaten, the centricity of the optical path might be a bit off, usually to the right as viewed.

At its worst, short of a broken compound prism, it will still yield an image which sees the standard movie frame width on the groundglass. You just won't be able to zoom back as far to cheat some extra apparent resolution through aquiring a wider image.

None of these issues are a big fix to take on but they do require some fine mechanical skills to undertake and a clean working environment to do the repairs in.

If you have to buy on the blind and find after you try it, you are falling short of infinity focus or have a soft edge, get back to us here and we can talk you through it.

Robert Bec · March 25th, 2009, 02:02 PM

this is it

Letus Extreme DOF adaptor "The ultimate 35mm film look" - eBay, Professional Video, Video Cameras, Cameras. (end time 28-Mar-09 19:07:37 AEDST) do you think the price is reasonable.

Bob Hart · March 25th, 2009, 10:39 PM

Robert.

On the surface of things, according to the images, the unit looks okay but are they representative images of the actual unit being auctioned or product illustrations from the adapterplace.com website?

Have a look yourself and make your own judgement.

Letus Corporation*::*Letus Bundles*::*Letus35 Extreme Starter Bundle

You have two days yet in which you can email the seller to clarify anything.

Short of catastophic damage from a major fall or an electrical falilure, there is not a lot which cannot be put right by a handy person with fine dextoral skills and patience when cleaning optical surfaces.

The published vimeo clips look fine to me. They appear to have been shot with the Nikon lens wide-open which will tend to mask any artifacts or defects in the groundglass movement. I could not see anything that concerned me.

Soft-focus panning movements across bright objects usually give the artifacts away if they are there.

There does not appear to be any one-sided edge softness. This is the signature of skewing the mount in an attempt to recentre an excessively offset optical axis.

Therefore the prism alignment seems to be within normal limits. Provided the unit is not abused during shipping I think it should work as claimed.

CAVEAT EMPTOR - I am also West Australian so it could be assumed I may be biased.

Robert Bec · March 26th, 2009, 01:56 AM

Letus Corporation*::*Letus Bundles*::*Letus35 Extreme Starter Bundle looks like a good deal my only concern which i haven't looked into is the GST i will pay on top plus taxes.
I will e-mail your fellow Western Australian and see what he comes back with.

Thanks Bob

Bob Hart · March 26th, 2009, 05:20 AM

The Aussie dollar has had a bit of a renaissance against the US dollar this past few days.

The gap has reduced a bit but if you buy in new from the US, you do have customs and GST to worry about.

If the motor does not have too many hours up on it the eBay one should be okay. What kills them is when somebody leaves the thing switched on and stows it away and flattens the batteries.

It takes a lot longer for the Letus to empty its batteries than a Mini35, so the motor gets a lot more continuous duty. Quyen runs them at a lower voltage to bring them into a continuous duty power range. For their original application in cellphones, they were to run at higher powers in short bursts.

My best practice recommendation when striking at the end of the day's shoot for any groundglass adaptor is to pull the batteries out and stow them, the work of a few seconds and some peace of mind.

It was best practice with electrically powered film cameras too because precious film could be wasted if the motor took off. I have a beautiful three minute but totally useless time and motion study of an automobile doorhandle on a rough road. It came about because a seat belt socket set off the camera run button.

With the battery out, if the appliance power switch is turned on by a bump or knock or pressure from padding in the cases, it does not operate.

Bruce S. Yarock · March 26th, 2009, 01:22 PM

Great idea, Bob. I'm going to try to remember to remove batteries from my Extreme.
bruce Yarock
Yarock Video and Photo

David Warrilow · March 26th, 2009, 07:26 PM

Hello Robert,

Re:Taxes in Australia - I got hammered when I brought in some Redrock gear to Oz. It was two separate items @ about $600 each - and they packed and shipped them as one parcel. That put the stated value of the parcel at over $1000 and therefore it attracted import tax. So my $1200 purchase ended up costing me over $1500 before they would release it. Had I known, I would have asked them to ship in 2 separate boxes with $600 on each - and ideally shipped on different days. The extra shipping would have been far less than the import tax I paid.

check out:
When buying over the internet
for info.

When I received my Extreme from the Letus guys last year, as I recall I didn't have to pay any import tax on it at all so it must have snuck under the magical $1000.

Cheers,
David.

Bob Hart · March 27th, 2009, 04:05 PM

In my post above I may have inadvertantly propagated a furphy ( strine for untruth ).

The Mini35 can be powered from a number of sources, usually a second camcorder battery of camera type. These can be had in varying endurance right up to V-mount style ENG batteries if the power dividing battery module has been fitted. So to say the Letus runs longer on a battery set is not necessarily correct.

The time it would take the Mini35 to pull down a big v-mount battery would leave the unit running a very long time and cause un-necessary wear and tear.

My recommendation on battery removal remains during storage or transport remains.

David Warrilow · March 27th, 2009, 05:48 PM

'Furphy'...I love that. I'm going to use that!

D.

Bob Hart · March 28th, 2009, 06:16 AM

Actually like some things oldendays Australian, the use of the word "furphy" is actually an opposite to fact, or so the story I have heard goes. Something older generation aussies used to do, a sort of a cockney throwback thing I guess.

Furphy is a man's name. He apparently was a maker of things out of metal, in particular cylindrical shaped iron water tanks which moved on wheels for transporting water. The tanker ends were of cast iron. On the castings, instead of ornamentations, curliques and scroll patterns, Furphy inscribed verse in raised letters.

I don't know if there were more than one but my recall is that the quotation was the "Good Better Best ---- " one.

Hopefully someone more knowledgable on things antique strine can put me right.

John Gibbins · April 10th, 2009, 07:25 PM

Sorry to jump in here, having trouble finding an answer anywhere else.
What are these two options for on the Letus?
Can't seem to find this info anywhere.

Bob Hart · April 11th, 2009, 12:23 AM

PL-Mount is a final evolution of the ARRI lens mount system, "PL" meaning " "positive lock".

OCT'9 is a lens mount standard which was devised in the former Soviet Union. Many of the economically priced used 35mm motion picture camera lenses available from eastern europe remain fitted with their OCT'9 mounts though some vendors are now modding them to PL-Mount.

Both are a bayonet style mount system with lugs to prevent lens twisting on the mount and a clamping collar, in the case of ARRI PL, precisely threaded and cut with clearances for the lugs to enable clamping in about a 60degree rotation of the collar. I have not studied the OCT'9 mount so cannot give you detailed comment on it.

The PL-Mount has a short shoulder and it is much easier to offer up and withdraw the lens from this mount than with the older ARRI standard and bayonet versions which had a much longer cylindrical shoulder which would bind and also wear due to the greater movement of the mount inside its receiver during offer-up.

March 25th, 2009, 12:21 AM	#1
Robert Bec Major Player Join Date: Aug 2007 Location: Sydney Australia Posts: 358	Letus back focus adjustment ring I like to purchase a used letus extreme do i need the Letus back focus adjustment ring or can i do without for now Rob

April 10th, 2009, 07:25 PM	#12
John Gibbins New Boot Join Date: Mar 2009 Location: Canada Posts: 15	PL or OCT'9 mount Sorry to jump in here, having trouble finding an answer anywhere else. What are these two options for on the Letus? Can't seem to find this info anywhere.

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March 25th, 2009, 12:47 AM	#2
Bob Hart Inner Circle Join Date: Dec 2003 Location: PERTH. W.A. AUSTRALIA. Posts: 4,476	Robert. You can do quite okay without the Elite backfocus. As long as your used Letus Extreme has not been interfered with and damaged internally or has electrical issues, you should be fine. If infinity focus falls short with the wider lenses like 35mm, 28mm or the ultrawides like 20mm and 14mm, then it can be adjusted. If you have the opportunity to try it on your camera before you buy, do so. Depending on how hard it may have been kicked and beaten, the centricity of the optical path might be a bit off, usually to the right as viewed. At its worst, short of a broken compound prism, it will still yield an image which sees the standard movie frame width on the groundglass. You just won't be able to zoom back as far to cheat some extra apparent resolution through aquiring a wider image. None of these issues are a big fix to take on but they do require some fine mechanical skills to undertake and a clean working environment to do the repairs in. If you have to buy on the blind and find after you try it, you are falling short of infinity focus or have a soft edge, get back to us here and we can talk you through it.

March 25th, 2009, 02:02 PM	#3
Robert Bec Major Player Join Date: Aug 2007 Location: Sydney Australia Posts: 358	this is it Letus Extreme DOF adaptor "The ultimate 35mm film look" - eBay, Professional Video, Video Cameras, Cameras. (end time 28-Mar-09 19:07:37 AEDST) do you think the price is reasonable.

March 25th, 2009, 10:39 PM	#4
Bob Hart Inner Circle Join Date: Dec 2003 Location: PERTH. W.A. AUSTRALIA. Posts: 4,476	Robert. On the surface of things, according to the images, the unit looks okay but are they representative images of the actual unit being auctioned or product illustrations from the adapterplace.com website? Have a look yourself and make your own judgement. Letus Corporation::Letus Bundles::Letus35 Extreme Starter Bundle You have two days yet in which you can email the seller to clarify anything. Short of catastophic damage from a major fall or an electrical falilure, there is not a lot which cannot be put right by a handy person with fine dextoral skills and patience when cleaning optical surfaces. The published vimeo clips look fine to me. They appear to have been shot with the Nikon lens wide-open which will tend to mask any artifacts or defects in the groundglass movement. I could not see anything that concerned me. Soft-focus panning movements across bright objects usually give the artifacts away if they are there. There does not appear to be any one-sided edge softness. This is the signature of skewing the mount in an attempt to recentre an excessively offset optical axis. Therefore the prism alignment seems to be within normal limits. Provided the unit is not abused during shipping I think it should work as claimed. CAVEAT EMPTOR - I am also West Australian so it could be assumed I may be biased.

March 26th, 2009, 01:56 AM	#5
Robert Bec Major Player Join Date: Aug 2007 Location: Sydney Australia Posts: 358	Letus Corporation::Letus Bundles::Letus35 Extreme Starter Bundle looks like a good deal my only concern which i haven't looked into is the GST i will pay on top plus taxes. I will e-mail your fellow Western Australian and see what he comes back with. Thanks Bob

March 26th, 2009, 05:20 AM	#6
Bob Hart Inner Circle Join Date: Dec 2003 Location: PERTH. W.A. AUSTRALIA. Posts: 4,476	The Aussie dollar has had a bit of a renaissance against the US dollar this past few days. The gap has reduced a bit but if you buy in new from the US, you do have customs and GST to worry about. If the motor does not have too many hours up on it the eBay one should be okay. What kills them is when somebody leaves the thing switched on and stows it away and flattens the batteries. It takes a lot longer for the Letus to empty its batteries than a Mini35, so the motor gets a lot more continuous duty. Quyen runs them at a lower voltage to bring them into a continuous duty power range. For their original application in cellphones, they were to run at higher powers in short bursts. My best practice recommendation when striking at the end of the day's shoot for any groundglass adaptor is to pull the batteries out and stow them, the work of a few seconds and some peace of mind. It was best practice with electrically powered film cameras too because precious film could be wasted if the motor took off. I have a beautiful three minute but totally useless time and motion study of an automobile doorhandle on a rough road. It came about because a seat belt socket set off the camera run button. With the battery out, if the appliance power switch is turned on by a bump or knock or pressure from padding in the cases, it does not operate.

March 26th, 2009, 01:22 PM	#7
Bruce S. Yarock Trustee Join Date: May 2004 Location: Pembroke Pines, Fl. Posts: 1,842	Great idea, Bob. I'm going to try to remember to remove batteries from my Extreme. bruce Yarock Yarock Video and Photo

March 26th, 2009, 07:26 PM	#8
David Warrilow Regular Crew Join Date: Apr 2003 Location: Brisbane, Australia Posts: 106	Hello Robert, Re:Taxes in Australia - I got hammered when I brought in some Redrock gear to Oz. It was two separate items @ about $600 each - and they packed and shipped them as one parcel. That put the stated value of the parcel at over $1000 and therefore it attracted import tax. So my $1200 purchase ended up costing me over $1500 before they would release it. Had I known, I would have asked them to ship in 2 separate boxes with $600 on each - and ideally shipped on different days. The extra shipping would have been far less than the import tax I paid. check out: When buying over the internet for info. When I received my Extreme from the Letus guys last year, as I recall I didn't have to pay any import tax on it at all so it must have snuck under the magical $1000. Cheers, David.

March 27th, 2009, 04:05 PM	#9
Bob Hart Inner Circle Join Date: Dec 2003 Location: PERTH. W.A. AUSTRALIA. Posts: 4,476	In my post above I may have inadvertantly propagated a furphy ( strine for untruth ). The Mini35 can be powered from a number of sources, usually a second camcorder battery of camera type. These can be had in varying endurance right up to V-mount style ENG batteries if the power dividing battery module has been fitted. So to say the Letus runs longer on a battery set is not necessarily correct. The time it would take the Mini35 to pull down a big v-mount battery would leave the unit running a very long time and cause un-necessary wear and tear. My recommendation on battery removal remains during storage or transport remains.

March 27th, 2009, 05:48 PM	#10
David Warrilow Regular Crew Join Date: Apr 2003 Location: Brisbane, Australia Posts: 106	'Furphy'...I love that. I'm going to use that! D.

March 28th, 2009, 06:16 AM	#11
Bob Hart Inner Circle Join Date: Dec 2003 Location: PERTH. W.A. AUSTRALIA. Posts: 4,476	Actually like some things oldendays Australian, the use of the word "furphy" is actually an opposite to fact, or so the story I have heard goes. Something older generation aussies used to do, a sort of a cockney throwback thing I guess. Furphy is a man's name. He apparently was a maker of things out of metal, in particular cylindrical shaped iron water tanks which moved on wheels for transporting water. The tanker ends were of cast iron. On the castings, instead of ornamentations, curliques and scroll patterns, Furphy inscribed verse in raised letters. I don't know if there were more than one but my recall is that the quotation was the "Good Better Best ---- " one. Hopefully someone more knowledgable on things antique strine can put me right.

April 11th, 2009, 12:23 AM	#13
Bob Hart Inner Circle Join Date: Dec 2003 Location: PERTH. W.A. AUSTRALIA. Posts: 4,476	PL-Mount is a final evolution of the ARRI lens mount system, "PL" meaning " "positive lock". OCT'9 is a lens mount standard which was devised in the former Soviet Union. Many of the economically priced used 35mm motion picture camera lenses available from eastern europe remain fitted with their OCT'9 mounts though some vendors are now modding them to PL-Mount. Both are a bayonet style mount system with lugs to prevent lens twisting on the mount and a clamping collar, in the case of ARRI PL, precisely threaded and cut with clearances for the lugs to enable clamping in about a 60degree rotation of the collar. I have not studied the OCT'9 mount so cannot give you detailed comment on it. The PL-Mount has a short shoulder and it is much easier to offer up and withdraw the lens from this mount than with the older ARRI standard and bayonet versions which had a much longer cylindrical shoulder which would bind and also wear due to the greater movement of the mount inside its receiver during offer-up.