Go Back   Steve's Digicams Forums > Digital SLR and Interchangeable Lens Cameras > Pentax / Samsung dSLR, K Mount Mirrorless

Reply
 
Thread Tools Search this Thread
Old Dec 15, 2007, 6:25 PM   #11
Senior Member
 
Join Date: Mar 2006
Posts: 116
Default

I started a battery thread a while back. Right now I use Moby rechargeable CRV3's and the Powermax brand of LSD NiMHs. So far both are great. I gotta say though, the full voltage of the Moby's (3.25 x 2 = 6.5 V) gives an oh so satisfying snap of the shutter and quick motor response - in addition to very fast flash recovery. Unless anything changes, I will use the NiMH's as backup, and the RCRV3's as main.

If you do go the RCRV3 route, make sure to get the kind that advertise a voltage suitable for digital devices (cameras) and that you also use a voltmeter to test them
anyway (both with and without a load).

I should add that I use a DS. I'm not sure if the other *ist / K versions are suitable for 6.5 V. I would check the DC input on the side of the camera to use as an upper limit of what is appropriate.
pwithem is offline   Reply With Quote
Old Dec 17, 2007, 10:31 PM   #12
Senior Member
 
lgbalfa's Avatar
 
Join Date: Jan 2006
Location: New York, NY
Posts: 125
Default

thanks everyone.

i bought the eneloop's on ebay.


lgbalfa is offline   Reply With Quote
Old Dec 18, 2007, 7:13 AM   #13
Senior Member
 
IntrepidWalker's Avatar
 
Join Date: Jan 2007
Posts: 177
Default

pwithem wrote:
Quote:
I started a battery thread a while back. Right now I use Moby rechargeable CRV3's and the Powermax brand of LSD NiMHs. So far both are great. I gotta say though, the full voltage of the Moby's (3.25 x 2 = 6.5 V) gives an oh so satisfying snap of the shutter and quick motor response - in addition to very fast flash recovery. Unless anything changes, I will use the NiMH's as backup, and the RCRV3's as main.

If you do go the RCRV3 route, make sure to get the kind that advertise a voltage suitable for digital devices (cameras) and that you also use a voltmeter to test them anyway (both with and without a load).
I would dearly love to go the RCRV3 route BUT with explicit warnings against their use in the user manual, I'm not too sure that I want to risk potential problems UNLESS there's a voltage controlled version that holds the output at no greater than 3V.

I've been happily using 2300maH NiHi batteries which give more that acceptable storage but am looking to try these
Hybrio AA batteries from Uniross which, although at only 2100maH should remain charged for longer which will suit users that use the camera on say a weekly basis.

Uniross Hybrio AA batteries are ready-to-use, meaning they can be used straight out of the package. The advanced technology used in Hybrio batteries allows them to retain a long-term charge (90% @ 6 months, 85% @ 1 year) - even if they are not used - and they can be recharged up to 500 times.

For power users, higher 2700 maH NiHi would be a better option.

IntrepidWalker is offline   Reply With Quote
Old Dec 18, 2007, 11:12 AM   #14
Junior Member
 
Join Date: Dec 2005
Posts: 20
Default

Interesting battery information from a reviewer on Amazon.

===================================

http://www.amazon.com/SANYO-eneloop-.../dp/B000IV2WAW
The News of LSD Has Been Slightly Exaggerated , January 6, 2007




By
NLee the Engineer (Nashua, NH) - See all my reviewsI was really excited when I first heard about the Sanyo eneloop LSD (low self-discharge] NiMH batteries. The promise to "maintain 85% of original charge after one year" sounds amazing. However, after reading Sanyo's Nov 2005 press release carefully, I learned that the claim is actually based on "simulation test when stored at room temperature of 20 degree C".

The rechargeable battery is an electrochemical device. Since most chemical reactions happen faster at elevated temperature, it is reasonable to expect the self-discharge rate of the eneloop to be also faster at higher tempeature. The question is: by how much? The following is my experiment:

I purchased two eneloop AA 4-pack on Jan 3rd. The packages were dated "2006-07", which means they were probably last charged in the factor nearly six months ago. The initial voltage is 1.31V for all cells. I then tested a total of five AA cells using the "Discharge/Refresh" mode on my LaCrosse BC-900 charger.

The first discharge cycle (at 250mA) yields the residue charge in those cells. The average of five cells came out to be 1476mAh. The spread is between 1388mAh and 1531mAh.

Next, the cells were fully recharged (at 500mA) and discharged again. The second discharge cycle yields the freshly charged capacity. Amazingly, the numbers all came out to be within 1-2% of rated capacity of 2000mAh.

Therefore on average, those five eneloop AA cells I tested have lost 26% of their original charge after nearly 6 months of storage. This rate of energy loss is about three times higher than what Sanyo advertised. However, it is important to point out that a typical NiMH cells will lose around 30% of is original charge within one month (Some brands, such as the Energizer 2500mAh, will loss 30% in one week). So the self-discharge rate of eneloop is still 6-7 times slower. Just remeber that they are best stored at temperature of 20 degree C or lower, if you hope to get the advertised self-discharge rate.

[Update on June 3, 2007]
In my 2-month self-discharge test using four different brands of NiMH cells. Hybrid and eneloop came up neck-and-neck!

Room temperature: 60-62 degree F (16-17 degree C). All capacities measured are average of 2-cells.

- Sanyo eneloop 2000, purchased Jan 2007.
Initial capacity measured: 2070mAh
Capacity after 62 days: 1796mAh (-13.2%)
(Note: my previous result for eneloop showed -18%, but I repeated the test and it did better this time)

- Rayovac Hybrid 2100, purchased Jan 2007.
Initial capacity measured: 2155mAh
Capacity after 62 days: 1859mAh (-13.8%)

- LaCrosse 2000, purchased Jan 2006.
Initial capacity measured: 1902mAh
Capacity after 62 days: 1417mAh (-26%)

- SONY 2300, purchased Sep 2004.
Initial capacity measured: 2210mAh
Capacity after 62 days: 1309mAh (-41%)

So neither eneloop nor Hybrid did as well as advertised, but they are still significantly better than previous generation of NiMH cells. So you can't go wrong with either brand.
michaeldwilson is offline   Reply With Quote
Old Dec 18, 2007, 5:23 PM   #15
Senior Member
 
danielchtong's Avatar
 
Join Date: Dec 2005
Posts: 2,888
Default

IntrepidWalker wrote:
Quote:
I would dearly love to go the RCRV3 route BUT with explicit warnings against their use in the user manual, I'm not too sure that I want to risk potential problems UNLESS there's a voltage controlled version that holds the output at no greater than 3V.
....

For power users, higher 2700 maH NiHi would be a better option.
I second what pwithem elaborated above.
My 3.15 V RCRV3 have been in my dL for around 8 months now after 8000 shots. I cannot be happier.
RCRV3 have been extensively covered and used in the Pentax fan site of Taiwan.
Somehow I do not feel comfortable with it on my K100D which has eneloop there.
One fundamental problem is still with the deviation of NiMH (1.2v) compareed with the designed 1.5v (as in regular Lit batt CRV3). That is way way below and that is the reason why K10D has proprietory batt rather than anemic NiMH.
Pentax manual has reason to be cautious about using RCRV3 the unregulated (and earlier) version of which gave almost 3.9V. The newer version of regulated one (nominally at 3v) hardly exceed 3.3v - well within 10% of the designed optimum voltage of 3v.


Daniel, Toronto
danielchtong is offline   Reply With Quote
 
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



All times are GMT -5. The time now is 12:09 PM.