Chroma - Lasercut Acrylic 4x5 Field Camera

Not too sure about the 'blackcurrant and liquorice' but looking good. :)



Given the publicity I think this is a must.

Do you have holes for the anti-rotation pins on common QR plates? ...seen a few videos with people using the small Manfrotto (200PL) plates with Intrepid cameras.

I confess it's a thread I dip into, but have you tried it with Horseman and Wista roll-film holders (for 6x7, 6x9, and 6x12)? Shen did a 6x17 extension back but that's probably a bit much.

Anyway, when are you taking orders? :D ...not that I need another 4x5, but... :)


As I see it, the closest competitor to my Chroma is the Intrepid. I'm never going to compete with Ebony/Chamonix/Shen Hao etc and never really set out to. In comparison to the Intrepid, my camera offers;

Full technical standard with independent movements (assuming I launch with that).

An upgrade path with modular components

Similar weight

Smaller overall

Choice of main body and bellows colour

Integrated magnetic zero points to ensure quick alignment

Similar price (£250 including pinhole lens after Kickstarter)


I was going to ask how Intrepid integrate their tripod thread but I can see on their site that they use a standard threaded insert with a plate over the top of it so that's simple enough. I could include guide holes for anti-rotation pins too if I can dig out the spec for them.

I haven't tried a rollfilm back but any that use a standard 4x5 DDS sized plate will fit.

As for taking orders, my intention is to launch the campaign in the next few weeks, once I've got a video and product shots together, along with some example photographs. I'd be more than happy to build one to your choice of colours from the campaign ;0)
 
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Personally Id stick to highlighting the specification of the Chroma, there's no need to do a "like for like" comparison to the Intrepid, mentioning the competition in your own promotional material seems counter intuitive to me.
 
Personally Id stick to highlighting the specification of the Chroma, there's no need to do a "like for like" comparison to the Intrepid, mentioning the competition in your own promotional material seems counter intuitive to me.

Cheers Nick. The comparisons are more for myself to help focus on the benefits. I won't include a powerpoint presentation showing the comparison ;0)
 
Ok, another question for the large formateers. Spring back, yes or no?

My design uses a removable ground glass which is attached with magnets. When it's removed, the DDS holder is held in by friction. I know I'm over thinking but it's getting close to a release and I'm wondering if it's going to be a pain having to put the ground glass somewhere while you take your shot? I'm concerned that, in the some of the places I've photographed landscapes, there would be nowhere to put the glass down safely and it would risk getting damaged.

I could add a pair of spring plates to the current design easily (once I sort out a good supplier for them!).
 
Springs over magnets. You're dealing with large format photographers so there's a risk that they'll set fire to the camera the moment they realise it involves the black magic of magnets.

More seriously, I'm always wary about things containing magnets because of the concern that it'll wipe my bank cards or screw up the memory card in my phone. Finding somewhere to put the glass when you've put a film back on shouldn't be a major issue, assuming you've used a bag to get the camera to your location in the first place.

That said, whenever I've played with my Sinar and put a film back in, I always seem to move the rear standard so I'm probably not the best judge of these things. :(
 
Springs over magnets. You're dealing with large format photographers so there's a risk that they'll set fire to the camera the moment they realise it involves the black magic of magnets.

More seriously, I'm always wary about things containing magnets because of the concern that it'll wipe my bank cards or screw up the memory card in my phone. Finding somewhere to put the glass when you've put a film back on shouldn't be a major issue, assuming you've used a bag to get the camera to your location in the first place.

That said, whenever I've played with my Sinar and put a film back in, I always seem to move the rear standard so I'm probably not the best judge of these things. :(

Cheers Dean. I'll market the magnets as magic voodoo that will make all of your exposures spot on, even Velvia 50 ;0)

The more I look at this back, the more I see why Intrepid use elastic!
 
The DDS is held in by friction; does this mean that you slide it in from the side, or push it in from directly in front? Either way, there seems to be a possibility of not getting it quite home, with the attendent problems of light leaks or focus being out (remember, with wide angle lenses the position is more critical than with long focal lengths). A spring loaded back means that the camera itself (on the tripod) is controlling the "push"; friction means that the photographer is effectively pushing the camera back forwards (with possibility of movement).

Like Dean, I'm wary of magnets, particularly as I carry bank cards on one side and mobile phone on the other.

The two weak points of the Chroma for me are the short bellows (less than Intrepid) and the magnets.
 
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The DDS is held in by friction; does this mean that you slide it in from the side, or push it in from directly in front? Either way, there seems to be a possibility of not getting it quite home, with the attendent problems of light leaks or focus being out (remember, with wide angle lenses the position is more critical than with long focal lengths). A spring loaded back means that the camera itself (on the tripod) is controlling the "push"; friction means that the photographer is effectively pushing the camera back forwards (with possibility of movement).

Like Dean, I'm wary of magnets, particularly as I carry bank carts on one side and mobile phone on the other.

The two weak points of the Chroma for me are the short bellows (less than Intrepid) and the magnets.

Thanks Stephen, I appreciate the feedback. Just to clarify the magnets, these are the same neodymium magnets that are used in phone and iPad cases to lock the device and keep the cover closed so they won't cause any damage to bank cards or mobile phones :0)

With regards to the back, it was designed with a friction fit but with the camera being lightweight you may be right about causing some movement when fitting it. I've got a few ideas in my head for a spring fit.
 
Just to clarify the magnets, these are the same neodymium magnets that are used in phone and iPad cases to lock the device and keep the cover closed so they won't cause any damage to bank cards or mobile phones :0)
We stayed in a hotel in Majorca a couple of years ago and t'missus insisted on carrying the door card around in her phone case. It took three days of me telling her exactly what the problem was as we went back down to reception to get the card refreshed before she stopped doing it.

Magnets - if no one can explain how they work, no one's telling me how they don't. :p
 
Ok, I'm happy to report that i've figured out the DDS holder design and am even happier that there isn't a major redesign needed :0).

Sorry @Strappy, it means fitting four more magnets but does result in a simpler and less movement-inducing method of securing the holder! I haven't drawn up the redesign yet but basically, I've trimmed back the top section of the rear standard that was creating the friction so that the DDS just drops into place. I've also added a very narrow strip of closed cell foam across the top edge in case there are any light leaks but I'm not expecting any. To hold it in place, the ground glass holder is lifted out of the camera (4 magnets hold it in place) then re-attached to 4 additional magnets around 30mm lower down the back so that the ground glass holder sits against the narrow raised lip on a standard DDS holder then is held tightly to the rear standard by the 4 magnets which, in turn, press the holder tight in place.

It will make more sense when I draw it up but it's a simple solution that doesn't need any additional moving parts and shouldn't have any impact on movement.
 
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Right, this is the idea;

1 - Ground glass in place for focussing/composition. Held in place with magnets furthest apart (all 4 corners of ground glass holder) and is how the camera is currently assembled.

Screenshot 2017-09-09 23.50.17.png

2 - DDS holder in place. Ground glass remove from camera, DDS holder dropped into place (no friction fit any more) and entire ground glass moved backwards 12mm and downwards 33mm to act as a frame, pushing the back of the DDS holder and in turn, keeping it flat and in place.

Screenshot 2017-09-09 23.47.04.png

The DDS holder is resting within a frame on all 4 sides so the ground glass acts as the rear-side support to keep the holder pressed flat against the rear standard.

Apologies to Dean, this actually adds an extra 6 magnets rather than 4 but it's a lot more simple to build than a spring back! The main benefits to this design are that it keeps the amount of material required to a minimum to maintain good strength and assembly time. The diagram looks more complicated than it actually is so I'd imagine it will only add 10 minutes to the assembly time. It also deals with my concern around where would I put the ground glass when I was ready to shoot.
 
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@stevelmx5 Earlier you though a roll-film backs would fit... but how would they be secured? Don't have one handy but they are quite deep (spool + a bit more) and the web suggests they weigh about 500-600g, which sounds about right and a bit much for friction fit? -- I guess it would come under nice to have, but...
 
@stevelmx5 Earlier you though a roll-film backs would fit... but how would they be secured? Don't have one handy but they are quite deep (spool + a bit more) and the web suggests they weigh about 500-600g, which sounds about right and a bit much for friction fit? -- I guess it would come under nice to have, but...

I've got a roll film back here. This method wouldn't support them as, like you say, the centre opening of the frame would need to be wider spaced (and not have a ground glass in the way!). I'm sure it's something I could add later on though using the existing magnetic mount points. I'd just need a square frame with embedded magnets to secure the back in place. When I get chance I'll measure one up.
 
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I would not trust a roll holder that was not positively locked in place, nor a dark slide that was not firmly under spring pressure. and positively able to withstand pressures of inserting and withdrawing the dark slide. I would not trust magnets.
 
I would not trust a roll holder that was not positively locked in place, nor a dark slide that was not firmly under spring pressure. and positively able to withstand pressures of inserting and withdrawing the dark slide. I would not trust magnets.

The magnets only keep pressure from the back. The film holder is surrounded on all 4 sides with a 3mm lip so it won't go anywhere when the dark slide is pulled out.
 
I'm still not convinced that having to find somewhere to put the ground glass while you're taking shots is a good thing. If it stays attached to the camera, like most 4x5 cameras, you don't have to worry about it, as soon as you put it down it's vulnerable.
 
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I'm still not convinced that having to find somewhere to put the ground glass while you're taking shots is a good thing. If it stays attached to the camera, like most 4x5 cameras, you don't have to worry about it, as soon as you put it down it's vulnerable.

That's still my thinking Nick. I could add a pair of spring plates to the back and make the ground glass holder into the sprung holder but I'm kind of trying to machine the entire camera out of acrylic for both the marketing factor and simplicity.
 
That's still my thinking Nick. I could add a pair of spring plates to the back and make the ground glass holder into the sprung holder but I'm kind of trying to machine the entire camera out of acrylic for both the marketing factor and simplicity.
Yes I do get that Steve and understand why youre going down that route and in a controoled evironment like a studio I'm sure it would be fine, I'm just going from experience. When we did the Cornwall trip earlier this year both me, Woodsy and Carl ended with our kit covered in seawater when the waves came in a little quick. I'm thinking that when you're taking shots on location the most likely place for the the GG will be on top of the camera bag, combine that with a particularly eager wave and I see the potential for a broken GG so if you can see a way of securing it on the camera that would be great, a little like the dark slide keeper on the Hasselblad Polaroid backs http://www.profilmdirect.co.uk/ekmp...elblad-polar-100-polaroid-back-used-308-p.jpg
 
Yes I do get that Steve and understand why youre going down that route and in a controoled evironment like a studio I'm sure it would be fine, I'm just going from experience. When we did the Cornwall trip earlier this year both me, Woodsy and Carl ended with our kit covered in seawater when the waves came in a little quick. I'm thinking that when you're taking shots on location the most likely place for the the GG will be on top of the camera bag, combine that with a particularly eager wave and I see the potential for a broken GG so if you can see a way of securing it on the camera that would be great, a little like the dark slide keeper on the Hasselblad Polaroid backs http://www.profilmdirect.co.uk/ekmp...elblad-polar-100-polaroid-back-used-308-p.jpg

I've already re-designed the back to use the ground glass as the rear-side retainer for the DDS holder (post #811) [emoji1303]

I completely agree that having a ground glass floating around next to the camera is asking for breakages, I'm also usually right next to sea spray/waterfalls/large drops so know the exact same situations!

In other news, I've assembled the focusing rack fully this morning using the newly designed rack/pinion gear and have to say that I'm not 100% happy with it. It could be down to my first draft gearing (drawn by eye and seeing what aligned on screen) or simply that the horizontal gearing is taking too much strain. After scratching my head for a bit I've realised that there's a much neater way of building an internal focusing design, using a traditional threaded bar running down the middle of the camera bed, front to back, then the focus is adjusted using a simple knob on the back like a Chamonix/Gibellini etc. I'm not quite there with my drawing yet but will upload some images when I am.
 
I've also made the decision to revert back to a more simplified rotating back as I used on a previous build where the whole rear plate is simply removed, rotated 90 degrees then clicked back into place. It won't make any major difference in the use of the camera but means less moving parts and bonded faces which can all lead to mis-alignments.
 
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A 45 degree rotated back... you're going for the Dutch angle then, Steve? ;)
 
Keep plugging away, Steve! In years to come, after your acrylic Chroma empire has risen, this thread will be preserved in the name of history ;)
 
Keep plugging away, Steve! In years to come, after your acrylic Chroma empire has risen, this thread will be preserved in the name of history ;)

Thanks Charlotte, I appreciate the support!

I've spent the last few days on a group chat with a range of bloggers/photographers/kickstarters' talking about our collective projects and plans. It's proving to be very useful as, apart from getting to know a good bunch of people, I'm finding that everyone has their own challenges and frustrations.

I'll get there soon :0)
 
Ok, serious question. I've been speaking to Stephen Dowling (KosmoPhoto) about his branding and it brought me back to an idea I had a while back. My design has a lot of flat acrylic faces so I was wondering about the interest in 'skin' set for the camera? Basically, they would be cut from vinyl in any design/pattern/text and fit exactly to the shape of the camera. I was thinking about the rear face of the film holder or the top face of the camera bed. I'd probably offer them as an additional purchase rather than include anything as standard with the camera but is it something that people would be interested in?

I'm clearly not aiming for the 'traditional' LF market (who will probably be sticking pins i voodoo dolls of me right now!) but there's a whole new market of film photographers that may like the complete customisation.
 
It might be something to look at further down the line (maybe involving specific designers, artists etc?) - having limited edition artist-designed skins would be so cool! Lomography do something similar with a few of their popular models, I think?

Also, I saw this and thought of you, Steve: http://www.donttakepictures.com/dtp-blog/2017/9/11/in-motion-darren-samuelsons-great-big-camera

I reckon my wife would have divorced me by now if I built a camera that big!

Good idea about the designers etc. Definitely something to keep on the table for down the line.
 
I was wondering about the interest in 'skin' set for the camera? Basically, they would be cut from vinyl in any design/pattern/text and fit exactly to the shape of the camera. I was thinking about the rear face of the film holder or the top face of the camera bed.

Hmmm... Nikon F or Ebony style skin, or a Leica red dot? :coat:

Or more seriously, perhaps a non-slip skin???
 
Ok, serious question. I've been speaking to Stephen Dowling (KosmoPhoto) about his branding and it brought me back to an idea I had a while back. My design has a lot of flat acrylic faces so I was wondering about the interest in 'skin' set for the camera? Basically, they would be cut from vinyl in any design/pattern/text and fit exactly to the shape of the camera. I was thinking about the rear face of the film holder or the top face of the camera bed. I'd probably offer them as an additional purchase rather than include anything as standard with the camera but is it something that people would be interested in?

I'm clearly not aiming for the 'traditional' LF market (who will probably be sticking pins i voodoo dolls of me right now!) but there's a whole new market of film photographers that may like the complete customisation.
I must fit into the 'traditional' LF market because the thought of a vinyl skin on my very own bright orange Chroma has no appeal at all.
 
Now all we need is a bloody camera to go with it. :D
 
Quick one for you knowledgeable boys and girls. I'm looking at the mount points for the front standard to the bed. My current design has 4 simple threads embedded in the bed at different points for different focal length lenses, like most traditional LF camera. The negatives to that method(and similarly flagged in a few Intrepid reviews) is that it's fiddly to mount the standard and there's a risk of dropping the bolt into a river/waterfall etc and you're then stuck. As a redesign, I'm thinking about having a slot running down the middle of the bed and leaving the bolt attached to the standard so it can be mounted by simply pulling the whole standard forwards and the bolt is then dropped into the slot instead, where it can freely slide to lock it into place for the lens being used.

Screenshot 2017-09-14 00.05.56.png

Screenshot 2017-09-14 00.31.17.png

The main benefit of this is that the front standard securing bolt stays permanently attached to the standard so can't go walk about as well making the process of mounting the standard to the bed much less fiddly. Any thoughts?

Cheers
 
Quick one for you knowledgeable boys and girls. I'm looking at the mount points for the front standard to the bed. My current design has 4 simple threads embedded in the bed at different points for different focal length lenses, like most traditional LF camera. The negatives to that method(and similarly flagged in a few Intrepid reviews) is that it's fiddly to mount the standard and there's a risk of dropping the bolt into a river/waterfall etc and you're then stuck. As a redesign, I'm thinking about having a slot running down the middle of the bed and leaving the bolt attached to the standard so it can be mounted by simply pulling the whole standard forwards and the bolt is then dropped into the slot instead, where it can freely slide to lock it into place for the lens being used.

View attachment 110529

View attachment 110530

The main benefit of this is that the front standard securing bolt stays permanently attached to the standard so can't go walk about as well making the process of mounting the standard to the bed much less fiddly. Any thoughts?

Cheers
That makes a lot of sense Steve, I like the idea of the captive bolt and the slot but I'd also like to see a marked 'standard' position if possible. So if you're completely new to LF cameras you can still set the camera up in a 'ready to go' normal position.
 
That makes a lot of sense Steve, I like the idea of the captive bolt and the slot but I'd also like to see a marked 'standard' position if possible. So if you're completely new to LF cameras you can still set the camera up in a 'ready to go' normal position.

Thanks for the validation Nick. I had the idea and then started thinking I must be missing something! I've got a 1mm rubber top surface to add to the bed and will be cutting in marked spaces for common distances so it's easier to go straight to the standard position for a particular lens.
 
Some better diagrams now that I've drawn the updated models. I'm really liking this method because it means that the threaded rod is used for fine adjustment once the lens is locked into the starting point so there's less need to move the rail forwards/backwards all of the time. Also, as there is a rail rather than 4 fixed threads there's a huge range of adjustment to cover loads of lenses.

Screenshot 2017-09-14 16.34.32.png

Screenshot 2017-09-14 16.33.07.png

The focusing knob is shaped like that so that the rear standard can rotate around when closing the camera up without it getting in the way.
 
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