Author Topic: Data loss when recording. (Read 17455 times)

Rickard · « **on:** August 03, 2011, 05:30:07 PM »

The new SanDisk Extreme Pro SDHC I 8 GB 45 MB/S memory card did not help solving the old data loss issue with my 981. On the contrary, the gaps in the recordings are now very frequent, more than once a second. In fact, my first 2 GB SD Extreme III gave much better recordings than the new card does. This issue may be caused by firmware upgrades as well, so it's actually not clear if it's just the card's fault.

The missing ping/data loss issue has disturbed me since the 981 became capable of recording some years ago, but I have heard the same issue appears with the newer models. I'm not sure everyone understands what this is all about, therefore I have attached two examples. The first image shows a log that got a zigzag shape because of missing data. The other image shows a slope that looks like a staircase.

Most of my latest images from wrecks are severely damaged by this problem, a very sad experience indeed. Am I the only one who have this problem?

Rickard

sonar2000 · « **Reply #1 on:** August 03, 2011, 07:01:31 PM »

Rickard......if you play back in humviewer or yellowfin does it also show the "gap"......Chuck

Rickard · « **Reply #2 on:** August 03, 2011, 07:09:00 PM »

Yes Chuck, It's visible in Humviewer and SiView, and I could see the gaps on the display while I was recording too.

Rickard

sonar2000 · « **Reply #3 on:** August 03, 2011, 07:16:40 PM »

OK, thanks, sounds like software (again). Hope they HB can get this fixed. Search and recovery can't take this kind of problem...but again we dont depend on one manufacture so have other units to help with the search.......
This problem does need some quick attention. Missing a good fish is importantand should not happen due to this error........
Chuck

Rickard · « **Reply #4 on:** August 04, 2011, 04:52:50 AM »

Yes, it's too bad if the units are not compatible with the newest and fastest cards. I understand you could miss a drowning victim if the image is distorted like my logs. I looked through a recent recording with the SDHC SanDisk Extreme 4 GB 30 MB/S card and the same settings and could see data loss just a couple of times per minute, not several times per second as with the newest card. I will solve this by simply using the 'old' card until HB comes up with a fix or tells us the units can't use the latest cards.

Rickard

ITGEEK · « **Reply #5 on:** August 04, 2011, 08:19:36 AM »

Rickard,
I don't know if this is related to your problem with the 981 or not:

But, since the 5.500 software upgrade on my 1197, when I view recordings, they are extremely
slow and the information looks choppy, as though there are gaps.
There are 3 forward speeds and it seems that images degrade worse the faster
the setting I use.

It's really useless and frustrating to look at a sonar recording the way the unit is working right now.
It was fine with the previous software version.

Rickard · « **Reply #6 on:** August 04, 2011, 10:06:33 AM »

I use the latest firmware for the 981, 4.950, which was released in July 2010. Replay with the unit looks the same with the 30 and the 45 MB/S cards. This means it looks ok at slow replay speed, but at the highest speed the pixels seem to be merged into big squares with the same intensity, thus the resolution is much worse at high replay speed. I have no idea if this is related to my recording issue, but it smells like the same problem category. Next time out I will do recordings with the 30 and 45 MB/S cards with the same settings at the same location to get a firm test of the card factor.

Rickard

Rickard · « **Reply #7 on:** August 04, 2011, 05:41:11 PM »

Tonight I scanned the same targets with the SanDisk Extreme and the SanDisk Extreme Pro cards and the results confirmed my previous impression; the fast SanDisk Extreme Pro causes much more data loss than the SanDisk Extreme does. A rough estimate tells that about 1/4 of all data could be lost with the Extreme Pro card.

The old data loss issue was bad, but this is far beyond what is acceptable.

I repeat, same settings, latest firmware.

Added; two snapshots from the same area. First image is from the SanDisk Extreme recording. The second is from the SanDisk Extreme Pro recording. Note that there is much fewer small bottom patches in the Extreme Pro image, although speed was i little slower when I scanned with the Extreme Pro card. Many details are simply gone with the lost data.

Rickard

ITGEEK · « **Reply #8 on:** August 05, 2011, 09:41:15 AM »

So,
What you are saying is that the unit is not capatible with the newest fastest sd cards?

RGecy · « **Reply #9 on:** August 05, 2011, 01:40:52 PM »

I have had some strange recordings lately as well and notice there are sometimes gaps in the recordings. Not as much as I see with some of your images. Usually mine will be right at the begining of the recording.

I think it is certainly an issue HB needs to look at in their software design. I would like to see them buffer the data to the unit, even have a large internal memory that would be able to store an entire days trip, then be able to export it out.

Robert

sonar2000 · « **Reply #10 on:** August 05, 2011, 02:11:17 PM »

Good idea....several other mfg's do that....
Chuck

Rickard · « **Reply #11 on:** August 05, 2011, 02:33:49 PM »

I have sent an inquiry on the card-unit-firmware compatibility issue to the HB support, I'll forward the answer to the forum.

Oh, a prompt reply has just arrived! They say the unit with the software will work with any SD and SDHC card, the same info as in the FAQ on HB's website. Either they haven't checked the Extreme Pro card, or there is something wrong with my system. I can reload the latest firmware and observe the effect, but since some data loss occurred with the old firmware also I don't expect this will help.

Rickard

Humminbird_Greg · « **Reply #12 on:** August 05, 2011, 04:25:52 PM »

Rickard,
I have already asked one of the Engineers to look into this. I don’t know if or when he will have the time to do so, but will report any results he has back here (if he does not post it himself).

Rickard · « **Reply #13 on:** August 05, 2011, 04:27:36 PM »

Quote from: ITGEEK on August 04, 2011, 08:19:36 AM

Rickard,
I don't know if this is related to your problem with the 981 or not:

But, since the 5.500 software upgrade on my 1197, when I view recordings, they are extremely
slow and the information looks choppy, as though there are gaps.
There are 3 forward speeds and it seems that images degrade worse the faster
the setting I use.

It's really useless and frustrating to look at a sonar recording the way the unit is working right now.
It was fine with the previous software version.

When I was fiddling with reloading the firmware I tested the replay function again and found that everything works well at all speeds in the BACKWARD direction! Fast forward results in a useless image.

Greg,
Thanks, hopefully this will be sorted out then! I will do more testing after resetting the unit and reloading the firmware.

Rickard

Rickard · « **Reply #14 on:** August 06, 2011, 04:11:42 PM »

I did two tests today after resetting the unit and reloading the latest firmware.

First, I tried recording the simulation to the Extreme Pro card, no signs of data loss at all.

Second, real recording on water, the same data loss phenomenon was there again. There were also several instances of data loss with the Extreme card, but far less than with the Extreme Pro card.

Conclusion; there is a hardware failure in my unit or the unit plus firmware is not fully compatible with the fastest cards. Also, the faster the card, the more frequent data loss.

The image shows a few locations with data loss (red dots) with the 'better' Extreme card. You have to be attentive to detect data loss occasions!

Rickard

RGecy · « **Reply #15 on:** August 06, 2011, 10:26:35 PM »

Rickard,

I think its in the software and the way it is processing the data. I have had some recordings where it will record a lot of extra data per ping as well. Used to be that the range was set and the amount of data recorded per ping was constant. Now it seems to jump around.

I have also noticed large gaps of data missing in the middle of some of my recordings. But, the reason I feel its in the software is the recording data in each file is all correct and not missing any numbers in sequence.

Greg, if you need any examples to send to engineering, I have plenty!

Robert

RGecy · « **Reply #16 on:** August 06, 2011, 10:28:20 PM »

Rickard,

I think its in the software and the way it is processing the data. I have had some recordings where it will record a lot of extra data per ping as well. Used to be that the range was set and the amount of data recorded per ping was constant. Now it seems to jump around.

I have also noticed large gaps of data missing in the middle of some of my recordings. But, the reason I feel its in the software is the recording data in each file is all correct and not missing any numbers in sequence.

Greg, if you need any examples to send to engineering, I have plenty!

Robert

Enufzed · « **Reply #17 on:** August 07, 2011, 12:11:58 AM »

Hey Robert,
Are you making "Doubly sure" Rickard & Greg get this post

GG

Rickard · « **Reply #18 on:** August 07, 2011, 03:22:31 PM »

Robert,

I have now tested the SDHC Extreme and SDHC Extreme Pro cards with two old firmwares, 4.180 and 3.940, and there is no effect on the gaps - they are as frequent as with the latest firmware. I regret I gave away my old 2 GB SD Extreme III card which I used until 2010. The recordings from 2009 and 2010 are all free from gaps and really sweet to look at in comparison to the present recordings! The SD Extreme II and III cards seem to be obsolete and impossible(?) to find in the stores anymore.

Forcing 10 ping/second doesn't help either.

Rickard

Enufzed · « **Reply #19 on:** August 08, 2011, 01:31:41 AM »

Rickard,
If you can post the exact name of the card you are looking for I will endeavour to find one here in Australia for you.
And thanks for all the great info.
Regards
Geoff

Rickard · « **Reply #20 on:** August 08, 2011, 05:03:43 AM »

Thanks Geoff, I'll remember your offer if I can't solve this here.

I think I have found a partial explanation for the gap phenomenon. There are SDHC cards and SDHC cards.... The SD Association do their best to sort this out here: HTTP://www.sdcard.org/developers/tech/speed_class/

My worst card, the SanDisk Extreme Pro is a SDHC UHS-1 card. R/W speed is 45 MB/s, but the UHS-1 type of speed class is not compatible with the 'old' type of speed class used for the SD and SDHC cards. Thus, one can't expect this card will work with a HB sonar since the HBs hardly meets the standard for HD video.

My second and better, but far from perfect card, the SanDisk Extreme is a 30 MB/s SDHC card with speed class 10, the highest in the 'old' speed class system. This card should work with the HBs, I think, but there are still gaps...

The card I gave away, a SanDisk Extreme III card had speed class 6 (20 MB/s), which has been optimal for my unit and my recordings this far.

I will search for a speed class 6 card and see what happens.

A critical question is; do the HB units have a Normal Bus or a High Speed Bus, this will determine if the max speed class is 6 or 10?

Rickard

Humminbird_Greg · « **Reply #21 on:** August 10, 2011, 04:32:19 PM »

Robert,
Which unit/software combination have you seen this problem with [make sure that the recordings were made with the same software]?
Is this when viewed on the unit or a 3rd party software?

Rickard · « **Reply #22 on:** August 11, 2011, 01:03:01 PM »

I found a 2GB SanDisk SD Ultra card, Speed class 4 (15 MB/s) and tested on water today - all gaps are gone!! I used the latest firmware update for the 981, 4.950. The newer and faster cards will rest in the drawer until there is a fix for them. Or perhaps my stepdaughter wants them for her camera?

Relieved...
Rickard

Rickard · « **Reply #23 on:** September 16, 2017, 08:22:08 AM »

Hi,

This post is a reply to the discussion in the thread: Hélix 10 mega G2 Towfish. I don't want to highjack that thread.

I made a comment there on gaps in the recordings, a persisten issue with these units since recording was introduced many years ago. At that time I thought it had to do with type of SD card, and maybe it has, but it could also be an effect of the automatic adjustments done by the unit when depth, range, signal level etc changes while recording. It looks as if the unit stops transmitting for a breif moment when changeing settings. Of course, there can be no data to record if there is no sonar activity. If that's so, why can't the unit be programmed to operate at the previous settings until the automatic settings are done?

Felix allowed me to present an example on the gap issue using one of his new images (with a Helix 10 mega G2). The gaps do not appear like empty spaces, they only show as strange texture leaps along a straight line. I have indicated all(?) gaps in the image below with white arrows pointing downwards. The gaps are located at the tips of the arrows.

Rickard

Bob B · « **Reply #24 on:** September 16, 2017, 03:24:41 PM »

Rickard .... just curious if these anomaly's can be observed when watching the unit screen and not recording....or do they only occur in the recording?

If it is only in the recording, my guess would be that it has something to do with the internal processing priorities. All operating systems have a priority of tasks to be performed and things like data recording may be at the low end of the priority scheme. Has the frequency of these data drops decreased as the processor speeds in the units have increased?

Rickard · « **Reply #25 on:** September 16, 2017, 06:59:12 PM »

Bob, I think the gaps are smaller and less frequent with my 999 than with my old 981. The 981 required specific SD cards to minimize gaps to an acceptable level, this seems less critical with the 999. I suppose this has to do with faster processer in the 999. But I was surprised to see so many and wide gaps in an image from a Helix. I can't say I have seen gaps in the display when not recording. As Felix writes, the display can freeze for a fraction of a second. This is probably the moment when a gap is created.

Rickard

abraquelebout · « **Reply #26 on:** September 17, 2017, 05:08:10 AM »

hi
I see this anomaly's observing screen, the screen freeze a short time and go again.....i must test depht in "manual" not auto to see if changing depht unit in "auto" can afect scrolling.

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