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Shearwater Teric vs. Perdix

Discussion in 'Computers, Gauges, Watches and Analyzers' started by Darcimus, Sep 4, 2019.

  1. outofofficebrb

    outofofficebrb HARRO HUNNAYYY

    # of Dives: 200 - 499
    Location: San Francisco, California
    Perdix, apart from the different form factor/size, are charging and the running costs. You do need to remember to charge the Teric. Should the batteries on the Teric completely die, you will lose tissue data. As it is a rechargeable battery, after many charges and discharges, the useful life and capacity of the battery will decrease. After a number of years (Shearwater estimates about 5 under normal use), you will need to have it replaced and it is not user replaceable. It's about $100 CAD + shipping to do this.

    For a Perdix, you don't need to worry about charging it and any AA form battery (SAFT, lithium, alkaline, Ni-MH rechargeable , etc) will work. You will get 40-80 hours of dive time (approximately) depending on which battery you use. All batteries are user replaceable. You will not lose tissue data when a new battery is being put in and it is also safe to do this during repetitive diving. I go on 2 big dive trips a year and average 50-60 dives each trip, 20-30 dives at a time falling under “repetitive”. 1 battery change per trip is all I need when using a standard alkaline AA. My long run average dive is 61 minutes and this is using AI. I have about 175 dives on the wireless transmitter and haven’t changed the battery yet.

    It is purely personal preference. Choose the one that works for you. Given @Marie13 ’s comments about sidemount and possible cave or tech, Perdix sounds like a better choice for you.
    NothingClever and Griffo like this.
  2. Larryjd1

    Larryjd1 Nassau Grouper

    # of Dives: 200 - 499
    Location: In my crease or underwater in Northern California
    If you are deciding between the Perdix and Teric, the good news is, you should extremely happy with either one. Think of it as deciding whether you want your favorite sports car with a manual or automatic transmission.

    For the poster above who writes that you might like the Perdix better for Sidemount than the Teric, I don't quite understand the reference since, as I write below, my best understanding is that they are functionally equivalent with the differences primarily in form factor.

    However, the person comparing the other products did bring up a valid point in that Shearwater is adamant about not providing GTR across multiple tanks, so you may want to consider that product if that feature is important to you. I would also question that it also does "automatic gas switching" as that was a feature of the Cochrane's that was either loved or hated - depending on who you spoke with. Shearwaters do not automatically gas switch, but they do take optimal gas available into consideration when doing calculations. You can search for more detailed info on both topics.

    When I was in a similar position, I had been using an Oceanic GEO 2.0 for over 150 recreational but decided to switch to a Teric when I started technical dive training in preparation for a 3+ week trip on the Odyssey diving the wrecks in Truk Lagoon this past July.

    Of the 96 dives I did there, the majority were EANx with deco obligations including gas switching for accelerated deco on the deeper wrecks. I was with friends who were experienced tech and cave divers as well as others that were new like me to tech - most using Shearwaters - so there was much discussion between dives about gradient factors and other usage factors and settings. From a capabilities aspect, they are functionally equal.

    With that background, here are more specific points to what you are asking:

    I wear my Teric as a watch when I am on dive trips, but not for regular daily use. I wear it on my right wrist when I am diving and my left when not. Switching it when putting on/taking off my wet suit means it is always on my arm and not subject to getting crushed, stepped on, lost or stolen. It is therefore always with me to view surface interval, dive planning or log info without carrying it around (and remembering to take it) or adjusting straps to wear on my bear arm once out of my suit. And, if you do buy the Teric, get a Nato strap so that if a pin breaks your computer will only flop back and forth and not drop to the ocean floor - much like the Perdix uses double straps. Actually, buy two straps so you can use a second as an extension in case you need it for your larger sized suits. I got orange just in case, but I think it looks good with the black bezel.

    I worried about battery life before my trip but was pleasantly surprised. Using a single transmitter, with 4-5 hours of diving per day, usage on the surface for surface analysis, dive planning, etc., with a brightness of Medium would consume around 20-25% of the battery per day. I tend to charge my li-ion batteries at about 50% so I would generally go 2 days or so between each charge, but probably could have gone 4 or more if I had to. I brought with me a 10,000 mAh wireless capable battery so I had the option to charge wirelessly if the supplied USB charging cradle failed for some reason during the trip. It also means that whichever charging method I selected, I could take my Teric with me and not have to leave it somewhere charging, which I usually did at night in my room, which was around 1.5 hours. On the Perdix side, I did read about people flooding the battery compartment for whatever reason, but felt that that was as likely to happen as an overall battery failure on the Teric - so in my mind potential battery issues were a wash.

    I disagree that the Teric is more subject to glass scratching as I was intending to get a protective covering before my trip, but just didn't get to it. So I was nervous at first, but after all those dives on the wrecks doing every engine room, squeezing through narrow areas and sticking my hands in literally holds of bullets to lift them by the fistful I have one little dent in the edge of the metal bezel that you can see if you look for it, but no scratches in the sapphire glass. Far better than most of the used Perdix's I see offered for sale here with far fewer dives and maybe not even as challenging conditions.

    For full disclosure, I have never used a Perdix. And, much as when we would discuss features and capabilities on the boat it sounded like we were talking about the same device, the menu systems just didn't translate the same. So I can only say that the Perdix did everything I expected it to do, and the menu structure was easy to navigate. But, I would expect a Perdix user to say the exact same thing. However, I could see where someone who was more familiar with one would think less of the other, simply because it was different than what they were familiar with and not because two buttons or four is any better or worse than the other.

    Usually in comparisons, like some of the posts in this thread, it is pointed out that the display is bigger on the Perdix, has more information and is easier to read - but I think that is like the project management truism that says you can have your project done well, done quickly and done inexpensively, but you can only have 2 of the 3. It can be done well and quickly, but it won't be inexpensive, etc.

    The Teric has a large font display mode with the minimalist of info, that is only available in Rec mode - if you have really bad vision. The Teric in normal size in the default configuration does have less info than the Perdix. However, as you can change the middle section to up to three segments including tank 1 and tank 2 into a single one of those segments (which I did not need or do) I had no problem configuring the device for something that worked well for me, even considering I was doing mostly deco and gas switching.

    As I had plenty of deco time on the hang bar to play with the available info and settings I would move the tissue loading graph into one of the segments as that was one of the frequent comments I read in comparisons, or I would move the SurfGF to the front screen for a time. Doing this just made it more convenient since like the Perdix the Teric allows you to view additional info not on the front screen by scrolling through via button press. Though to be fair, I believe the Perdix can roll through the info with fewer button pushes, but I didn't find what I was doing was onerous.

    My last point of customization is that you may never experience what you like until you use it a while - it has that many options. I read the full manual when I got it and started using it during my training and regular rec diving. Five months later I read it again during the plane ride over. I then read specific sections again over the three weeks and 96 dives as I became more familiar with actually doing technical diving and deciding better the information I wanted to see and where. And when I got back, I reread many of the posts on this board, especially from the Shearwater account that helped me understand even more minute details about configuration such as if you populate the three segments with things other than your current 02% it automatically moves to the bottom of the display, giving you almost a fourth customizable segment.

    I should also add that my eyes will be 60 later this month and I had no problem reading the display even with it in Medium brightness.

    Bottom line, you will be happy with either one.

    And much like my fast, cheap, good truism, there isn't only one correct answer here either - just what works for you.

    Hopefully the information helps you. I know I have benefited from what others have posted as I had decisions to make.
    MichaelMc likes this.
  3. Mike1967

    Mike1967 Manta Ray

    # of Dives: 100 - 199
    Location: Victoria, Australia
    According to Shearwater, SM mode is apparently coming in a future firmware upgrade.
    ScubaWithTurk likes this.
  4. Ben_3

    Ben_3 Barracuda

    # of Dives: 100 - 199
    Location: Canada
    I too am considering either one. I would be curious to know how many actually wear the Teric as an everyday watch or only on dive days. (not considering those who work pro and dive every day). Dose anyone think Shearwater will come out with a new perdrix in the next year or so with a new screen (amoled) like the teric...? Last question how dose the Teric and battery fare in cold water 4,5'c?
  5. -JD-

    -JD- Eclecticist ScubaBoard Supporter

    # of Dives: 50 - 99
    Location: Greater Philadelphia, PA
    Just purchased a Teric, but would have preferred the Perdix AI (mostly for the swappable battery) if not for the better efficiency of use of the display on the Teric.

    For the near future at least, I'm using it in OC Rec mode, Standard/Small/4-line display format AI, without gas switching. On the Perdix approx 1/3 of the display area is used for simultaneous NDL and Safety Stop info in a (IMO) wasteful way. The Teric, uses a modal format that presents that information sequentially, but clearly and occupies < 1/6 of the total display area.

    Up top I have mode, battery, depth and ascent info

    2nd Line I have NDL/SS (and Deco in extremis) and Tank Pressure/GTR (combo)

    3rd Line i have PP02, TTS, and Delta+5 so I can monitor risk-factors by default, but this line can be scrolled through the other info screens with one button.

    Bottom I have my Dive-Time and Gas-type

    And I leave the compass up on the outer ring all the time so I have orientation at a glance.

    While I'd like to see them implement a couple more combo displays (PP02/CNS% and TTS/Delta+5), as it is, I have a ton of info, legible, clearly labeled, and at-a-glance.

    FWIW, I'm 51 with now, aging-eyes. The Teric is very visible to me at "normal" wrist-view distance. YMMV
    Ben_3 likes this.
  6. loosenit2

    loosenit2 Solo Diver

    I went trough the same decision making process you did last year; ultimately I went with the Teric, and have not regretted it. As a middle aged man with appropriately deteriorating eyesight I was concerned about being able to see the Teric. That fear was totally unfounded, because of the screen sharpness I have no problem whatsoever reading the screen, including seeing two tank pressures ( i routinely use 2 transmitters).

    I don’t use it as a daily wear watch, but when I am on dive trips I wear is all day. I find that it will last about two, maybe 3 days between charges. On a multi-day trip you do have to take the computer and the transmitter and cable, the whole thing in the included case is about the size of a baseball. Typically I throw the charging cradle in a box with my camera eqipment to minimize space.

    It is not a smart watch.

    The Teric is a little bit easier to navigate with the 4 buttons vs 2 button interface but that is not a huge deal.

    Can’t imagine you would be disappointed with either option.
    Ben_3 likes this.
  7. BackAfter30

    BackAfter30 Angel Fish

    # of Dives: 50 - 99
    Location: Denver
    I bought my Perdix a year ago. I wanted a Teric. At that time I couldn't read all info on the Teric without my readers, I could read the Perdix. Perdix it is! Today I can't read all lines of my Perdix without readers. Deteriorating oldster eyesight should be a consideration when choosing.
    Ben_3 likes this.
  8. lexvil

    lexvil Loggerhead Turtle

    # of Dives: 1,000 - 2,499
    Location: jamestown, ca.
    I’m well past 50 and I use the Teric, on trips I wear the Teric as a watch even on the days I’m driving to dive for every day of regular life I don’t want to subject it to that. Just sold my Perdix AI, that is a great dive computer but I find the Teric better for me.
    Ben_3 likes this.
  9. Jay

    Jay Need to dive more!

    # of Dives: 100 - 199
    Location: Melbourne, OZ.
    for q1: Poll: How you use your Teric (and more) ...

    Yes, I think a Terdix is an obvious 'next' for SW. I'm surprised we've not yet seen it.

    IDK an exact answer re cold water .... but:

    From the manual:

    Screen Shot 2019-09-06 at 9.40.42 am.png

    SW have said that extreme temperatures will harm the battery's longevity. I don't think I drilled down to what 'extreme' meant but I would assume at or out of the limits of short-term temp range.

    I would assume something inside the long term temperature range parameters has no or minimal effect.
    Ben_3 likes this.
  10. RayfromTX

    RayfromTX Student Of Gas Mixology Staff Member ScubaBoard Sponsor

    # of Dives: 200 - 499
    Location: Hill Country of Central TX
    I wear one of each on my right arm. I dive sidemount. I find myself mostly glancing at the Teric. I'm late 50s and use readers in my mask.
    1isNone likes this.

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