To keep this thread under control, I'm consolidating info by adding this introduction about the Little Bramper:

What is it? The Little Bramper is a Bulb-ramping intervalometer that uses bulb mode to precisely control the image exposure (with a precision of 0.001s). The user can then smoothly vary the exposure during the time-lapsing session, enabling flicker-free exposure transitions (e.g. day to night, night to day, approaching thunderstorm etc.). The reason Little Bramper exists is simply because dSLRs cannot natively provide silky smooth exposure variations. Using Little Bramper is a manual, interactive process in which you study your histogram and decide whether you need to increase of decrease the exposure. If you like the idea of bramping, but insist on it being automated, you may be interested in Shutterdrone's `Lightrails' which has a built-in light meter. There are other bramping devices out there, but I can't vouch for them as I have no experience with them. I have sufficient confidence in the Little Bramper that I'm prepared to put my non-existent reputation on the line and offer it to fellow enthusiasts.

What else does it do? Little Bramper can also be used like a regular intervalometer (i.e. in modes other than Bulb). Most notably it offers arbitrary 0.001s precision intervalometry (e.g. sub-second) and ramping of the Intervalometry (causes your time-lapse to accelerate/decelerate). Annoyingly, neither of these functions are available in workhorse intervalometers, such as Canon's TC-80N3.

Despite its name Little Bramper actually provides considerable freedom in how you use it. Very little is hidden from the user. For example, your total time-lapse exposure range can be greatly expanded by incorporating `advanced' techniques based on photographic reciprocity, such as ISO-stepping and the adding/removal of ND filters. These can expand your exposure range to over 15 stops if you have a nice camera and good ND filters. Bulb-ramping alone can offer about 7 or more stops, limited only by the longest exposure times you're prepared to tolerate. For technical reasons the shortest bulb exposures are about 1/10s. The 'Holy Grail' goal is about 20 stops - enough to get you from direct sunlight to a star-filled sky.

Can I get one? Little Bramper is something I do in my spare time and is under continual development. Things are subject to change. If you're interested in it, read on, leave comments, or send me a PM. Personally, I will keep on bramping, and if there's sufficient interest amongst other time-lapsers I will continue making batches of them. The second batch should be ready in late September 2010.



Works on Canons (users of Rebels will additionally need a hotshoe-to-PC adapter)
Does not work on Nikons
Untested on Olympus, Sony, Pentax


You get everything necessary to start shooting immediately (except for the eternal gotcha; batteries not included):
Actually, if you use a Canon Rebel you will need a hotshoe-PC adapter. I cannot provide these at this time.

1x Little Bramper board (with LCD and keypad)
1x _your_model_ Camera connector (extras are $6 each)
1x connector for PC socket
1x Battery holder
2x extension cables
1x terminator plug - allows you to use some features of LB (sub-second intervalometry and interval ramping) with modes other than BULB. Not shown in picture.

Assembled: SOLD OUT $75 + Shipping ($7 insured domestic. $14 uninsured international)
Kit: SOLD OUT $65 + Shipping (you solder components to board - quite easy)


The second batch should be ready in September 2010.


If you're interested in obtaining a unit when they're available, please send me a Private Message [PM] with subject 'Little Bramper' and include your:

Full name:
Email address:
Whether you want a kit or assembled unit:
Model(s) of camera: (this is for connectors. First connector is included in price. Extra connectors are $6)
Your country:

No commitment on your part. I'll add you to the spreadsheet and get back to you when things are ready. Eventually, ordering will be through an e-store, rather than Timescapes.org.

Example time-lapses taken with Little Bramper:

(password: Golden)


(password: Yerba)


Some basic instructional videos:
(password: LB)
http://vimeo.com/12589301
http://vimeo.com/12590632
http://vimeo.com/12590412
more advanced stuff to come ...

KIT assembly instructions are here
Cheatsheet is here.
Full manual is in the works.

Cheers,
Tom.





Finally, the original content of this post ... (to preserve the causal fabric of forum space-time).




Foolishly I said I'd whip up a simple pure bulb-ramping intervalometer by the weekend - I have 1 minute left. Mostly a copy & paste affair (both soft- and hardware), but the core timing method is rather different to my other intervalometers, and the interactions between Bulb and Interval times proved to be rather more complex than I'd initially thought. However, it seems to be straightened out now. Its main distinction is that both Bulb (B) and Interval (I) now take values in milliseconds.

In terms of a possible kit; it's all through-hole parts. Really very few of them. Not a difficult soldering project at all. Gave up on the idea of a basic button interface and stayed with the keypad. No need to make things harder just to make it look superficially simpler.

You are amazing Tom. Please bring toys over to show off ASAP!

Will the device handle 'normal' intervalometer functions as well?

Come on Thomas,

Show us a video of this beauty in action please.

Lucky you didn't haven't an earthquake to contend with .. Seriously good work!

You'd have to list those 'normal' functions. If you set ramping to zero, it behaves like a basic intervalometer. Doesn't do bracketing, or self-timer...



Had my alarm clock gone off this morning I'd have tried a night-day. My first field test was a disaster - maybe try again this evening...



Right. We had a small tremor in Ann arbor last year - actually woke me up. Amazing how the Earth can move.

I was in the mountains east of Santiago on Saturday night when one of the larger after shocks hit. First time I've felt a wobble standing on solid ground...for the big one the night before I was in a building. Feeling solid ground wobble is just plain weird!

fantastic Astro... is there a Parts list that i can get to go to my local supply store and fill or does mouser have everything ??
thanks in advance

kd7

The main problem there is that the microcontroller needs to be programmed with the firmware. What I suggest is that I simply make bags of all the parts (programmed microcontroller, nice PCB, LCD, keypad + all other bits) and just sell these as a kit.

Nevertheless, I shall write up a 'bill of materials', and for the 0.0001% of people prepared to program the PIC 18F2520 microcontroller themselves, I'll supply the hex file. In the past I've bought the LCDs from a guy in Ann Arbor - very reasonable price in bulk, hand delivered the same day (any standard 20x4 HD44780 compatible LCD should work). Keypads are from ebay/China - correct pin-out must be ensured here. I wouldn't recommend getting these sorts of parts from Mouser, as they're much more expensive. The prototyping board I used in the pictures below is from Radioshack (276-168). RadioShack is hideously overpriced, but this board was really quite handy.

Unfortunately I won't have these available until April - traveling the rest of this month. Had an irritating Toyota bug (dangerous and hard to reproduce) but seem to have that sorted out/circumvented.



I soldered together this prototype for an upcoming trip to San Francisco - hopefully shall time-lapse with Delrious. The camera connects to this gadget via standard 3.5mm stereo miniphone jacks. The function and wiring for this connection will be described later.



works with other LCD displays, like this giant one,



The final PCB will be home-etchable, I believe - but I shall be getting some 'professionally' made. The total parts cost for the soldered prototype in the pictures is not less than $30. Add to this the cost of the PCB, about $10 I'd imagine. Batteries not included.



Here's a night-day test I did with this gadget the other week. Not more than 15 stops; light pollution -> Sun on snow. I think I started at ISO 3200 (Canon 5DII) , and the quality was really rather good. Password: bramp



Cheers,
Tom.

You rock!!! Please stop by sometime this week for show and tell

Sure, any day other than wed. Earlier the better.

i'll buy one

Really appreciate your effort to make this available. Thank you

Soon we'll just be saying - your Worshipfullness....

You guys in Ann Arbor are now getting nearly a full day of my time. See you both in mid-May.

great work... put me on the list for one, and let me know when they are ready...

got my soldering iron all warmed up and waiting... whoo hoo !

kd7


ps i will need a 2.5 mm plug for canon

Put me down for one!

Me too!

and me! You will have to set up manufacturing base in China at this rate

Had a conference in San Francisco last week. Delrious very kindly showed me around some of his excellent time-lapse spots. SF really is a great city for time-lapsing.

Here's some raw bulb-ramping footage taken using the gadget;


password 'Golden'. The glitch near the beginning is just user-error.


password 'Yerba'

Now to get those PCBs made ...

Brilliant and no flicker at all ! or did you have to tweak it post using anti flicker software?
How many boards are you getting for your first batch? Cost of gadget ? Do we have to reconfirm our orders?