Sunday, October 28, 2012

Nikon DSLR battery project, 4S LiPo testing

Project test continues with 4S LiPo battery (Orion 14.8V 6400mAh). Only D200 camera was powered. I used four diodes as voltage dropper (1N3879 switching diode). This solution is only temporary, more sophisticated one would be low loss switch mode voltage converter....

camera setup
Nikon D200
300/4.5 lens (at max aperture)
raw images used
menu: high ISO NR, off
menu: long exposure NR, off
"M" mode used
bulb exposure selected
camera at room temp, approx +23C

exposure setup
MC36 trigger used
delay 10sec
exposure 60sec
interval 62sec
no limit in image count

Results (27th Oct)
Diodes heat up a bit during testing, without heat sink used. Test was stopped, when voltage per cell approx at 3.5V level (some cells were 3.2/3.3V, two last at 3.6V, slightly uneven discharging). Totally 472 images were taken. It corresponds to three times more images, than in 3S LiPo 2100mAh test setup.

Friday, October 26, 2012

Utö nightsky, milky way

In the the beginning of October 2012, we had a company's photography club trip to Utö. It is a small island, in southern Finnish archipelago.

Expected clear sky there, for astro imaging. Expectations were not completely fulfilled. Occasionally sky was clear and milky way visible. Definitely a place, where you need to visit again some day...

Milky way, Utö 10/2012

Tuesday, October 23, 2012

Nikon DSLR battery project, 3S LiPo testing

I put the Orion 3S 11.1V LiPo cell (2100mAh version) to test. Nikon D200 is directly fed with this battery, no EN-EL3E used at battery slot. Small fuse of 2.5A is used in series to protect camera... I made the test without MB-D200 battery pack.

Power cord I took from my Nikon EH-6 AC supply. A sacrifice to science was made, and wire cut with scissors :-) Starting voltage at 3S LiPo battery, was 12.4V. I will at least run test down to 11.1V, maybe even a bit below that, if D200 still operates correctly.

Settings in the camera, were following:
Nikon D200
300/4.5 lens (at max aperture)
raw images used
menu: high ISO NR, off
menu: long exposure NR, off
"M" mode used
bulb exposure selected
camera at room temp, approx +23C

exposure setup
MC36 trigger used
delay 10sec
exposure 60sec (1min)
interval 62 (1min 2 sec)
no limit in image count

Results (23rd October)
Sequnce was run, until voltage under load was 3.5V per cell (overall 10.5V). Totally 145 images were taken. There is capacity increase noticed, when compared to 48 images with single EN-EL3E  and 91 images with dual EN-EL3E (with MB-D200 battery grip).

Results (24th October)
Orion 3S Lipo battery was charged again. Now it took bit longer than last time, approximately 75min to full charge. Test settings were same as above, totally 149 images taken.

Sunday, October 21, 2012

Nikon DSLR battery project, LiPo charging

Both batteries are now charged, all went OK as expected. No heating was noticed in the battery, when touched by hand. During 4S LiPo charging, charger itself heated (not still too hot to touch).

Following figures below, show the main data during charging. 3S LiPo was charged with full current (2.1A). Even it was defined higher current - 5 Amps - for the Orion 4S 6400mAh LiPo, approximate value was 3.3Amp.

Charging data for 3S 2100mAh LiPo
Charging data for 4S 6400mAh LiPo

Nikon DSLR battery project, used equipment

Here is a brief view, to selected equipment - what I use my LiPo battery project:

Microcontrolled charger (Robitronic LD15z)
Orion LiPo 3S 11.1V 2100mAh battery
Orion LiPo 4S 14.8V 6400mAh battery

Drawback in the first battery, is the output voltage range. In full charge (3*4.2V=12.6V) it can feed Nikon D200 without any voltage converter. When battery is discharged, voltage drops below the specified level. It remains to be seen, whether it affects to camera operation.... This battery equals to capacity, usually found in pro-DSLR's, like D3/D4.

The second one, provides approcimately three times capacity than first one (3S 2100mAh version). Output voltage in the 4S version, is too high to  be connected directly to D200. Fully charged battery provides approximately 16.8V. Nikon own power supply EH-6 provides specified 13.5V output voltage. Connecting battery directly, might blow up my camera, and I do not want it to happen. So in first phase of test, I propably will make diode connection is series. That will drop voltage approximately 3V (5*0.6V). Then output voltage would vary somewhere in range of 11.8...13.8V.

Microcontroller charger

Orion 3S LiPo battery

Orion 4S LiPo battery

Thursday, October 18, 2012

Nikon DSLR battery project, EN-EL3E measurements

Short time ago, I made a test to check - what is approximate capacity of a single or dual EN-EL3E battery capacity (in taken images, before imaging totally stops). Basic test setup was following:

-Nikon D200
-300/4.5 lens (at max aperture)
-raw images used
-menu: high ISO NR, off
-menu: long exposure NR, off
-"M" mode used
-bulb exposure selected
-camera at room temp, approx +23C
-MC36 trigger used
-delay 10sec
-exposure 60sec (1min)
-interval 62 (1min 2 sec)
-no limit in image count

It is not fully same, as camera used in low temperatures, like -20C. I would estimate, that in the cold environment - maybe 50...70% of this coud be achieved.

results were:
D200 Used with single EN-EL3E (without MB-D200) -> best result 49 images.
D200 Used with two EN-EL3E (with MB-D200) -> best result 91 images.

Nikon DSLR battery project, introduction

Time to take a new project. Many times I have noticed on the outside, that Nikon D200 pulls out effectively the full charge out of batteries. The supplied EN-EL3E is not provided with a big capacity. In cold temperatures like -20...-30C, image count could be as less as 20...30.

Insteadt of using older lead-acid technology, I selected Litium technology. This provides higher capacity in same volume & weight. The downside of this, is higher price tag.

Purpose of this project, is to provide capacity at least 3 times, compared to normal setup with Nikon D200 drived with single or two EN-EL3E LiIon batteries. I selected LiPo (litium polymer) battery type, because those are easily available in stores selling stuff for RC hobbyists. Microcontrolled chargers, provide accurate charging of LiPo battery. More will follow, when project continues. Stay tuned :-)

Nikon EH-6 secrets, part 6

Small update to blog post, since new Nikon consumer & pro DSLR's have been released and already on the market:

-D800/D800E: not compatible to EH-6 (uses EH-5B; with adapter EP-5B).

-D600: not compatible to EH-6 (uses EH-5B; with adapter EP-5B).

-D4: compatible to EH-6B, but requires EP-6 adapter (dummy battery with EH-6 input connector)